41 Limited transmission and rear end fluid change

[Matt Harwood]

After a discussion elsewhere (http://forums.aaca.org/topic/292643-maintenance/) I figured I'd share what I did to get the Limited's rear end and transmission back into shape. Last year, after considerable research, I decided to use 85W90 in both the transmission and rear end. I found a suitable GL4 oil that would work and since 90W was the recommended viscosity in the manual, I figured that was the smart choice. Shortly thereafter, I noticed that it was really tough to get the transmission into 1st gear after it was warmed up. I installed new bushings for the linkage, and while it helped, it was still a struggle to get first gear at a stop light. I felt like I was abusing the hardware. Something was wrong and it wasn't like that before. That meant I screwed it up. Fortunately, that also narrowed down the list of suspects.

At the same time, I think the rear end got louder. This was harder to quantify, since all I did was top off what was already in the rear end when I got the car. It took a surprising amount to fill it up, which suggested that it was very low on oil, but I don't really remember noticing that it was loud prior to that. We took one long, high-speed tour out to a WWII re-enactment and I recall that I was thinking the rear end was humming much more than I remembered. It's always hard to quantify when a car is new to you and you don't have a sold baseline, but it just seemed noisier than I think Buick engineers would have wanted on a limousine. Not awful, but it was there. You know how you can hear things that regular non-car-people don't? It was like that.

 

Fist thing I did was call my friend Doug Seybold who said they use 85W140 in everything they restore, so that's what I initially gravitated towards for a refill. All of the 85W140 is GL5, which might concern some folks about wear and tear on "yellow" metals like the brass in the synchros. So I did some more homework and found that Royal Purple 85W140 gear oil has none of the sulfurs that attack the yellow metals, so it should be 100% safe. Being a synthetic should also help, so I ordered a case (expensive--about $100 for six bottles). But then there was that discussion I linked to up above, and on the advice found in that thread, I instead went and got some GL4 140-weight gear oil from O'Rielly's Auto Parts ($18/gallon). They have it on the shelf, so it's not hard to find. Make sure you get the right stuff because they also have 85W next to it. So GL4 140W extreme pressure hypoid gear oil seems to be the smartest bet.

 

I finally carved out enough time to spend a few hours on the car. We're in the middle of moving into a new shop, my kids are wrapping up the school year, business is busy, the lawn needs mowed, the house needs a bathroom remodel, etc. It all gets in the way. But we have two new lifts in the new shop, so I figured that I'd give them a stress test with the big Limited. Today I put it up in the air and got busy.

 

Buick up in the air at the new 25,000 square foot Harwood Motors shop. We haven't
moved in yet but a few cars from inventory have come over recently to free up space

 

The first thing I did was pull the drain plug on the transmission and let it drain for a while. The stuff coming out seemed clean and in good order, so no worries there. That was the fresh stuff I put in last summer. I moved to the rear end and removed the bottom bolts first, then worked my way around the circle, leaving the bolts above the halfway point in place, just loose. Oil started to flow out of the holes in the bottom, which I expected. It was FULL of metal particles, giving it a weird metallic sheen. Uh oh...

 

Someone had obviously been in the rear end not too long ago and sealed it up with RTV, which is OK--that's how I will put it back together. But it took a screwdriver and a hammer to gently pry the rear end off the housing. More fluid came out and I let it drain for a while as I refilled the transmission. That part went smoothly, although I was surprised by how much the transmission took--about 1/2 gallon, which was more than I recall from last time. Meh, whatever, as long as you fill it to where it is just weeping out the fill hole, you're OK. It's incredibly easy if you get one of those $10 pumps they sell that screws into the top of the oil bottle and a little clip holds it in the fill hole.

 

Transmission very easy to drain and fill

 

Buttoned up, I moved back to the rear end. I used some paper towels to gently push the remaining fluid out the bottom hole and get it all out. Yeah, a lot of swirling metal in there. I'm pretty nervous now. I also found a few brass shards in the rear end cover, but I have no idea where they could have come from--there's no brass in the rear end. They were big enough chunks to pick up with my fingers. Odd, but I wasn't as concerned about that since they seemed so anomalous and were stuck to the inside of the rear end cover, not sitting in the bottom of the housing. Move on.

 

Rear end with cover removed and oil draining. Seems OK...

 

Definitely a 4.20 (4.18) rear end; pinion gear teeth look OK

 

First thing I did was hose it all down with brake cleaner and get a look at the gears. They SEEM OK, maybe some minor wear, but nothing terribly noticeable. They aren't wrecked. I also confirmed that this is the original rear end, with 4.20 (actually 4.18) gears inside, as noted by the 11-46 stamped into the pinion gear (46/11 = 4.18). I finished mopping it out with more paper towels to be sure I got all the old oil out. I took the rear end cover, which was gunked up with RTV silicone sealer, to my handy bench grinder with a wire wheel, and knocked it clean in about three minutes. We're moving into a new shop and I finally have the space and facilities to set up all my restoration tools and equipment, so jobs like this go MUCH faster.

 

Teeth seem OK. Not perfect, but not destroyed. I think I'll be OK. What do you think?

 

All cleaned up with brake cleaner. Seems good.

 

While I was at it, I cleaned up the original bolts and lock washers, which were gunked up with more RTV. I didn't clean the heads since I didn't want to knock off the plating (if any). I note that the four top bolts did not have lock washers, but that seemed incongruous to me, so I found four and made sure each bolt had a lock washer on it.

 

Rear end flange all clean

 

Bolts and washers cleaned up and ready to reinstall

 

I also had to clean off the housing itself, which was likewise smeared with goop. I put an old T-shirt over the gears and most of the opening so that the goop and any stray wires from the wire wheel attachment on my angle grinder would not fly into the housing. Again, three minutes later, sparkling clean mating surface! Odd to see how crappy the weld between the two halves of the axle housing is. No wonder they leak...

 

Internals protected while I clean goop off the housing

Flange all clean and ready to be sealed up again

 

With all that done, all that was left was to reinstall the cover and fill it up. I bought some black RTV in a pressurized can with a nozzle, which is a lot easier to work with than a tube. Gaskets are available, but my 5.0 liter Mustang's service manual specifically says NOT to use a gasket and just use RTV sealant, so I figured if it would work there, it would work here. Besides, that's how it was before and the rear end on the Limited was not particularly leaky, so I figured it was OK. I put a nice bead all around the perimeter of the housing and encircled each bolt hole, then gently pressed the rear end cover into place. The RTV instructions say to just put the bolts in finger-tight, then let it cure for 24 hours, then torque them to spec. I put a dab of RTV on the bolt threads to help seal them (note that the holes go all the way through into the reservoir). Also note that the rear end cover has a handy notch below the bottom center bolt hole to indicate where the bottom is so it is installed correctly. The fill plug should be at about two o'clock just above the halfway mark.

 

New RTV, curing, waiting to be torqued and filled. Note notch below bottom bolt
to orient rear end cover correctly.

 

Anyway, the 24-hour cure time slowed me down. I haven't put the oil in yet (it's about 18 hours later as I write this), so I'll go back to the shop later today, torque everything down, fill it up, and go for a test drive. I'll report back this evening or tomorrow!

 

PS: Also found that the master cylinder is leaking. Ugh, I guess that's next...

 

Edited May 28, 2017 by Matt Harwood (see edit history)

[1939_Buick]

4 hours ago, Matt Harwood said:

I finally carved out enough time to spend a few hours on the car. We're in the middle of moving into a new shop, my kids are wrapping up the school year, business is busy, the lawn needs mowed, the house needs a bathroom remodel, etc. It all gets in the way. But we have two new lifts in the new shop, so I figured that I'd give them a stress test with the big Limited. Today I put it up in the air and got busy.

 

Buick up in the air at the new 25,000 square foot Harwood Motors shop. We haven't
moved in yet but a few cars from inventory have come over recently to free up space

 

Looks good

I have corrected your post as to what is important when it comes to pre war Buicks 

[Spinneyhill]

The metal in there would be ringing alarm bells for me. Where did it come from? I would be esp. suspicious with that RTV around. The novice and the untrained often use too much and the little beads on the inside go places you really don't want them when you want oil to flow and lubricate. I would have dismantled it to look at all bearings etc. and all the clearances. It could be a subtle misalignment that corrected now, with new bearings, will save much grief soon. I have had this in a motorhome diff. - silver sheen in the oil, differential removed, one bearing was slightly misaligned and had started to eat away its side and the mounting side, making excessive play and increasing wear rates in various places. You also clearly have a problem having noticed extra noise and then all the loose metal in it.

 

I don't know Buicks so I will ask some dumb questions.

 

Are the differential bearings OK? All in adjustment?

 

Are the pinion bearings OK? In good adjustment?

 

Is the pinion set up with shims? Is the clearance correct? If it is set up with shims, could s.o. have put brass one(s) in there and one or more have have escaped?

 

Is the end float correct on the drive axles?

 

Are all the crown wheel bolts tight? I have had the experience where they were all loose and still held by their bent up tabs, until one broke its head off.

 

Did you photograph the wear pattern on the crown wheel? Some experts here might pass comment. Did you look at all teeth on crown wheel and pinion to confirm they are all in good shape with similar wear patterns?

 

Suggest you get an oil analysis done. It might give a good indication of the type and thus source of the metal.

 

Seriously, you need to find the source of that metal and deal with it, don't just cover it up again. It won't get any better while the gremlins work on it over the summer.

Edited May 29, 2017 by Spinneyhill (see edit history)

[Matt Harwood]

Spinney, while I appreciate your attention to detail, your knowledge, your experiences, and your advice, I'm not particularly inclined to do a full tear-down of the rear end at this point. Your comments are well-taken, believe me, but I am usually someone who believes in Occam's Razor; that is, the simplest explanation is usually the right one. This car came to me two years ago with a quiet differential. My first move was to fill it with a gear oil that was too thin, and when it started to make a faint noise audible only to me, I decided to change it for something thicker. The foremost expert on these cars said, "90-weight is too thin, we use 85W140 and it works much better." The metallic particles in the oil are a bit concerning, but my experience says it's an inevitable part of use--they're not chunks, but even more fine than the metallic particles in metallic paint. My 1993 Ford Mustang LX5.0 has nearly 36,000 race miles on it. Race miles. Open track sessions. Autocross. A few SCCA match races at the local level. Every three outings I would change the Mobil 1 gear oil in it and every time there would be a metallic sheen in the oil as it sat in the pan. 36,000 race miles later, that car is still running its the same gears and Trac-Lok limited slip with no ill effects. The tiny chunk of brass I can't explain, but there's no brass in the rear end of this car and even if there were, it wouldn't be a chunk, it would be a flake and it would have sunk to the bottom of the housing, not stuck to the top of the rear end cover above the oil level. Odd, but so out of place that I'm not going to go looking for its source because the simplest explanation suggests that it got there while the rear end was open last time, not as a result of self-destruction. A wound devastating enough to peel off a chunk of brass this big would do damage that would still be felt and heard, continuously, wouldn't you think?

 

Here are some hi-res photos of the ring gear and spider gears so you can see that the faces of the gears are not worn in a scary, abnormal way. In fact, now that I compare this gear set to the one in my '41 Century (link below), they look pretty much the same and the aforementioned experts, the Seybolds, signed off on it being more or less the way all '41 Buick rear ends look after all these years (click to embiggenate the photos).

 

 

 

The rear end housing is attached to the torque tube and the pinion is pretty much permanently pressed into the housing. That's why changing a Buick rear end is a major ordeal--there's much more than just swapping gears and/or pumpkins. Separating the torque tube and the rear end housing is tough and putting it back together is another challenge altogether. There are bearings holding both the inner and outer ends of the axles in the housing, and those are roller bearings in cages, held in place by the caps you see. Here's what my '41 Century's rear end looked like coming apart (it was healthy):

 

http://www.harwoodperformance.bizland.com/1941buick/042904.htm (if you read through the entire process and look at the photos, you'll see that there isn't much to go wrong in there--no shims or spacers, no brass).

 

So which is more likely: a car that was run for an unknowable amount of time before I owned it with low rear end oil and then filled with oil that was too thin being a little noisy because of it? Or some catastrophic failure waiting in the wings that only waited for the thinner oil to be installed before revealing itself, but only as symptoms that mimic oil that is too thin?

 

I agree that prudence is often required, but doing a full autopsy on this rear end at this point probably isn't necessary. If it's still noisy (and again, the noise was audible only to me and even then I couldn't be positive it was an unacceptable level of noise) with the thicker oil, or if it gets worse, well, then I might go in after it and talk about replacing bearings and other parts that are likely pure unobtainium on a 1941 Buick Limited. But at the moment, the gear teeth on the pinion and the ring gears look decent, if not perfect, but probably like they should for 70,000 or so miles of use. Then again, this is a 75 year old car with a history of being used as a car behind it. My experience and my gut say that the oil was too thin and made it a little noisy.

 

I will definitely let you know how it turns out after a test drive on Monday, weather permitting.

[Dynaflash8]

Let us know if it is quiet after you're all done and on the road.  Looking forward to hearing the news. 

[Bob Engle]

The early 30"s Buicks have brass spherical thrust washers behind the spider gears.  I would have removed the center block and checked the thrust surfaces on the spiders.

 

Bob Engle

[Spinneyhill]

Sure, it is your car and you know it better than I. But I have never seen a sheen on the oil like that from a diff. or gearbox or engine, other than the aforementioned motorhome (which turned out to have a problem) and the front axle of my 4WD mini tractor and I was pretty concerned about that.

 

I hope you are right. All the best with it.

[Matt Harwood]

Well, the rear end took a surprising amount of oil (at least a gallon) and became quiet again. The transmission slips into first gear effortlessly, hot or cold. I drove the car at varying speeds for about 45 minutes, including several 60 MPH runs on the highway and it remained quiet. It's not silent, but I don't think it ever was, and it's considerably better than it was. Now I'm thinking that a lot of the whine that I hear now might be tire noise, although the radials seem very quiet. It no longer seems to be coming from the back of the car. I can induce some rear end noise by stabbing the throttle and creating lash in the drivetrain, but that's not real friendly and isn't how one usually drives anyway. After 45 minutes of varied driving, I came back and aimed my temperature gun at the differential cover and it said 141 degrees, which seems cool but nice to see that it wasn't cooking itself--cool is better than hot. It does not appear to be leaking. We'll see if there are any drops under it tomorrow, but I don't expect any. I'm satisfied with the result but will keep an ear out for any unusual noises--you guys have me paranoid now.

 

As if I needed more of that when driving an old car...

Edited May 29, 2017 by Matt Harwood (see edit history)

[Dynaflash8]

My mechanic had 90W in his garage, so I got him to drain my rear and install it in the '39.  Now that I'm not at home I can't drive it to see how it sounds.  It's always had some rear end noise since I installed a 3.9 rear from a junkyard Century many, many years ago.  Sounds wonderful on your Limited.  I know if I ever get one again I'll not remember the oil you used, so I might have to write.

 

Good going.

[FLYER15015]

Matt,

Your diff will really sing when the inner pinion bearing looks like this.

This came out of a Dana 135, under our 06 Jayco, (Chevy C-5500).

Coming back from Florida last year, she started singing about Nashville.

At Kansas City the radio would not go any louder.

By Denver we thought we would both go deaf.

I pulled it apart in the driveway and took it to "The Differential Man" in Colorado Springs.

A fantastic guy that I would highly recommend.

4 hours later she had 4 new bearings.

Put her back in the next day using a Tx jack.

Been quiet now for 8k miles.

 

Mike in Colorado

[Janousek]

Nice write up Matt.    I'm with Bob that they had brass thrust washers between the spiders and sometimes between the sidegears and housing.  

 

All the old Motors books recommend 140 wt in this stuff.  They aren't lying either as I used to think I was helping with modern 80-90 and all they did was leak and make noise.  

I run a quality 140wt safe on white metals oil in stuff after 30'.  Most of the pre 30's get a 250wt safe for white metals.  

 

Better plan on 4 wheel cylinders to go along with a leaky master cylinder.  While your in there the shoes will need to be relined and drums turned.  You know the drill for a can of worms.  

[Janousek]

I forgot to mention that diff whine is during acceleration only and on coast the singing sound will go away.    Might want to check the outer wheel bearings when you do the brakes.  Seems like I replace a set a year that are decent/safe bearings but make noise.  They would have minimal or no lubrication if they were ever run low on gear oil.  

 

With your new shop get a chassis ear setup so you can pinpoint some of this stuff quicker.  

[Daves1940Buick56S]

18 hours ago, Matt Harwood said:

Well, the rear end took a surprising amount of oil (at least a gallon) and became quiet again.

I must admit I was surprised to see the filler plug up so high in your photo. On my 1940 Super it is about the 4 o'clock position, but I am not familiar with Limiteds. Does a gallon agree with the shop manual?

 

Cheers, Dave

[Matt Harwood]

10 hours ago, Daves1940Buick56S said:

I must admit I was surprised to see the filler plug up so high in your photo. On my 1940 Super it is about the 4 o'clock position, but I am not familiar with Limiteds. Does a gallon agree with the shop manual?

 

Cheers, Dave

 

That's where it was when I took it off and it has the special notch in it on the bottom bolt--it wouldn't make sense to have that notch on the second one up from the bottom or something. I don't have my manual handy. I'll double-check.

[Brian_Heil]

What if that pan notch was meant to be at the 12 o'clock position?  That would put the fill hole at a more typical location/height but about at the 8 o'clock?  As high as where you have it, wouldn't the rear lube height flood the tubes and out to the seals and out to the backing plates?  Just a thought.  Never seen one that high.

[Matt Harwood]

Well, craps, it looks like you guys are right. The nice thing about having two of these cars sitting here is that it's easy to check. Sure enough, it looks like I put the rear end cover on incorrectly. Well, I didn't, but whomever had the car before me because I just duplicated what he did. Looking closely at the inside of the rear end cover, you can see the oil level just below the fill plug and the other Limited here in the shop has the fill plug below the center line of the housing. Why they would put the little notch on there in an incongruous place like that, I don't know, but it sure looks like it needs to be turned two or three bolts clockwise.

 

Guess I'm going in there again. I suppose I'll tear it all the way apart this time and look at the guts. It's not broken, but this is my chance to fix it until it is. Bah.

 

Edited May 30, 2017 by Matt Harwood (see edit history)

[Dynaflash8]

It's a really difficult job to set up a rear end if it's taken too far apart.  Be very careful and go by the book.

[Janousek]

Get a dial indicator on the ring gear to check the backlash.  Most vehicels are .004-.008 but a lot of this older stuff can have over .010" when worn.  Just make sure you put it back where it was or it will probably make noise.  The pattern is set into that gearset and not a good idea to change it.  

 

I probably wouldn't remove the carrier just the spiders/side gears and inspect outer wheel bearings if the carrier feels smooth,  decent backlash on ring gear, and you have preload on the carrier bearings.   Good backlash/wear pattern in the teeth before you dissasemble means the bearings are in good shape.  Once the bearings start to fail is when the backlash grows.   If you throw a dial indicator on it and it reads .025" then your in for new bearings/crush sleeve and that is when setup is critical.   

[Brian_Heil]

Janousek just read my mind, keep the pattern but check your lash this time.

 

You could think of adding a magnet like more modern cars have too.

 

 

[MrEarl]

Great write up Matt, great pictures.

I think what needs to be for sure lined up are the areas I am pointing to below? Then the gears will have plenty of clearance and the fill hole will come out right.

 

 

 

[Brian_Heil]

13 minutes ago, MrEarl said:

Great write up Matt, great pictures.

I think what needs to be for sure lined up are the areas I am pointing to below? Then the gears will have plenty of clearance and the fill hole will come out right.

 

 

 

 

That is why Mr. Earl is a Moderator  . . . . . .

[smithbrother]

He is the MODERATOR because,,,, they PAY HIM BIG BUCKS.  Millions, and Millions. 

 

Some folks are just worth Millions and Millions.

 

Dale in Indy

[FLYER15015]

Please note the oil line shadow in post #22, which is just at the bottom of the oil filling plug.

DUH ????????????

[MrEarl]

2 hours ago, Brian_Heil said:

 

That is why Mr. Earl is a Moderator  . . . . . .

 

Just an armchair mechanic with benefit of high res pictures to see things probably clearer than Matt was able to at the time.  And I'm sure we've all not been able to see the forest for the trees before. 

 

2 hours ago, smithbrother said:

He is the MODERATOR because,,,, they PAY HIM BIG BUCKS.  Millions, and Millions. 

 

Some folks are just worth Millions and Millions.

 

Dale in Indy

 

Seriously? Guess I better get management my address so they can get me a check  in the mail. 

[Joseph P. Indusi]

Some years ago I asked a mechanic who specialized in differentials and transfer cases what the level of the lube in the rear axle should be.   He said the bottom of the filler plug should be about the level of the middle of the axles shafts.   I think that confirms where Matt is re-installing his rear axle cover.  Good catch by MrEarl on the cover tabs!

Joe, BCA 33493

[smithbrother]

Mr. FITTY FO,

 

Seriously, NO,  sad, very sad, hehe

 

Dale in Indy

[billorn]

On 5/31/2017 at 5:24 PM, FLYER15015 said:

Please note the oil line shadow in post #22, which is just at the bottom of the oil filling plug.

DUH ????????????

 

Go away for a few days and look what happens!!! LOL! Theres a thread on the general discussion about mistakes youve made. Looks like nobody here in the Buick department but the original poster makes mistakes when they work on old cars. Hope the brakes didnt get wet but it should be ok if the seals held. Big cars like this tend to be overbuilt and I bet the gears are OK. Seriously I cant be the only one who makes mistakes in the garage becasue I can see myself doing exactly what the original poster did. You take something apart and you put it back the way it was thats how you work on old cars. Unless you were there when it was new its hard to know whats right and whats wrong. Making fun of someone for making a mistake any of us could have made is wrong though. We are here to help right?

[Gary W]

I was wondering if  you could comment on my last post, page 12, where I used Texaco's MEROPA 680 Gear oil in the transmission and differential.  Thank you!  Gary

[MCHinson]

Gary,

 

Is that product labeled as rated for Hypoid or Extreme Pressure? I am certainly not an expert but the 140 GL4 product certainly works well for me. It shift easily and silently. You will read a bit more about it in the next issue of the Torque Tube II.

[Gary W]

Thanks Matt...I'll have to look it up.  I don't know.  Never gave it a thought in the past.  It works great in the old Fords that I just used it again.

[DonMicheletti]

The '38 manual calls for SAE 90 wt. The transmission calls for 140

[Gary W]

I know I've repeated this on my running restoration thread, and on the Maintenance thread.  But I thought it was relevant:

 

 

If someone out there could help me clarify:

 

My MEROPA 680 Gear oil is  ISO 680 ,  AGMA is  8 EP.

The Lube chart that Larry furnished above calls for  SAE - 160  EP Gear Oil in the Transmission and Differential. (Summer)

 

 

So I researched tonight and this is what I found:

 

This is the data for the MEROPA 680 Gear Oil.  You see it is AGMA Grade 8 EP /  ISO Grade 680.

 

 

 

This viscosity chart clearly equates ISO 680 with AGMA 8 with SAE 140 Gear Oil 

 

So the question.......  Can I still use the MEROPA 680 in the Buick Transmission and Differential?  I've been using it over 24 years in my Ford's Steering Box, Gear Box and Differential.

[billorn]

No offense but people have been saying that 140 lube weight is what theyre using in there Buicks. Why bother with something else that may or may not work and nobody has any experience with it in there Buicks? Even the OP said he was going to use something else and changed his mind at the last minute because of advice from these people. Sounds like you are hoping you have a solution to something that isnt a problem. Cars in the 1930s were alot different than Model Ts so why try to make Model T oils work unless you have a few 55 gallon drums laying around your trying to use up.

[Gary W]

Just trying to learn, that's all.  I have no horse in the race.

This car is new to me, so I ask a lot of questions.  I'm heading out this morning to get the gear lube.  

[billorn]

Any update to this? Im wondering if it was still quiet even with less oil in it. Im over due to change the fluid in the rear of my Olds and its probably the same as this.

[Matt Harwood]

I guess this is as good a place as any to update status. I got tired of seeing my Limited sitting in a corner of the shop permanently broken. Oh, wait, I didn't finish this differential oil change story, did I? Well, sadly, I let people goad me into taking the carrier bearing caps off to see if everything was OK (which it was, of course). However, during reassembly, I accidentally dropped one of the caps and the mounting ear broke off, rendering my Limited 5000 pounds of ornate paperweight in the middle of my shop. I had the guys help me push it into the corner where it has been sitting for the entirety of the summer, unused. Missed quite a few events this year, including a long-distance driving tour that the '29 wouldn't have handled but was ideal for something like the '41. Worthless to sell, worthless to keep.

 

Of course, it remains 100% my fault, and I accept that. However, let this be a warning to those of you who want to share information here--there will inevitably be someone telling you that you're screwing it up and that you should do something different than you're doing. My advice? Tell that person to roll it up real tight and cram it. A simple oil change has turned into a massive goat-fark that may yet cost me several thousand dollars to correct (anyone got a spare '41 Limited rear end laying around? No? I didn't think so.). This was my fault, but I shouldn't have gone looking for problems where none existed.

 

Anyway, I found a machine shop willing to try to make a new one. Try being the operative word. They're going to reverse-engineer it using the other side as a guide. Purely a time+materials basis and no guarantee of success. I could bolt it together and start driving and the whole thing could grenade, who knows?

 

So leave the parts alone if they're not broken, no matter what anyone else says even if their condescending tone makes it seem like they know something you don't.

[MCHinson]

Matt,

 

I have missed reading your posts on the forum. Glad to see you back. Sorry to hear of your misfortune. I don't have a spare 1941 Limited Differential laying around but if anybody in the world does, I would bet on it being Dave Tacheny. Have you tried calling him?