philipj

Overdrive Information 38 Buick...

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I wonder if the mounting in the torque tube is not stiff enough?

 

The torque tube will sag slightly with the weight of the OD in the middle. It has to, to mobilise its strength in bending. In addition there is the weight of the OD in the middle bouncing up and down. A heavier torque tube plus front and back mountings might help. The OD was originally made to be bolted on the back of a big, stiff lump of metal, perhaps supported (mine is) so the bearings are not made to handle any slight misalignment of the output shaft (or input shaft for that matter).

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Lloyd used large and beafy flanges to handle the weight and flexation of the torque tube.   Do you have one of Lloyds overdrive units.  Lloyds use of a chain coupling to correct any possible flexation.   I took a good look and the only possible weakness in my opinion was in the rear flange  that attaches to the back of the OD unit.  Physics still can not be fooled.   Mass in motion  always rules.   So the issue has reasonable points.   Evidently Lloyds design’s have stood the test of time.   My opinion is that if he had a problem, it would have become obvious and either fixedor discarded.   Time seems to have shown his design to be more than adequate.   Yup, I am a advocate of his idea and equipment design.   His design has made it nice to drive those wonderful old cars of yesterday.  I’ve done two options to speed up my two cars.  Lloyds overdrive and Bob Pipkins original third member ratio swap.   Lloyds is less expensive and most flexable.   The third member swap is more expensive and less flexable in operation.   Bob’s swap is less obvious  but  nice in its ability not to show the change.   So, as a friend used to say,  lay your money down and take your chances.   If you are’t sure, contact one of our happy users  of the options, drive them around a bit and that will give you the answer you need.   My driving consitions dictate  minimum of  60+  mph with engine rpm limits less than 3000 rpm.  

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My OD system is mounted very close to the original third member.   Maybe an inch or two closer is possible but  the OD is mounted within the last quarter or third of the torque tube .   I’d like to send you pic of my OD system when it was finished.  I’ll. attach it to give you an idea its position to the third member.  Its ready for the trip back home to install and ‘ride’ with the crowd.   65 mph with 2350 rpm all day. 

244860FF-6A11-4CE3-B099-8011E2347F4F.jpeg

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Hi Jack.   Yes there is a sealed bearing in the front of the OD unit.   Also there is the  same style in the output shaft.   So what ever you use, it should not go where it should not go.   The original OD units bolted to the transmission directly and  “might” not have the separation available for lubrication’s.  Sealed bearings came on streem in the ‘40’s so that type of seperation was not available then.   This just gives us a good idea to chase down.    There must be some ‘old’ transmiission rebuilder who can answer this very good problem. 

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Originally the front bearing of the OD was the rear bearing in the gear box. The main shaft projected from the gearbox into the OD unit. In the drawings and photo's I have I can see no way for oil to get through other than through the gear box rear bearing and it is more than 20 years since I overhauled mine so cannot remember. I note, however, there are cutouts in the gaskets between the gear box and the adapter (solenoid mounting) plate and on the other side of the adapter plate.

 

So the adaptation would clearly have to provide a replacement plate, input shaft and bearing on the front of the OD unit.

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Getting late as I have to go to the ‘Doc’s early (10am) for my quarterly check up.  He likes to see me as all my stuff is very good for a 75 year old.   But he can’t explain the stroke and 1.5 heart attacks.  Hmmm.   

           I will send some pix of the rebuild.  Input and out put bearings, moditocstion of the input shaft to have the input sprocket etc.   Tomorrow !!

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Here are some pix of the rebuild back in Sept.   The output shaft is splined and you can see the sealed bearing supporting the output shaft. Also there is the planetary gear and free wheeling clutch assembly.  I don't see the pix I attached ? ? 

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3 hours ago, Jim Nelson said:

I don't see the pix I attached ? ? 

Me neither. Have you put them in the bar where it says "Drag files here to attach"? If so, next step is to put the cursor where you want the picture to appear in your post, then click on the picture you want there and wait a moment and it will appear. You can resize it by clicking on it and dragging a corner box

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OK,  Here goes again.  Somehow I did it OK when I was talking about Century out board axel bearings.

3ED544B9-81D3-42BE-A337-794AA15D5098.jpeg

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8DA0B58A-979D-4610-AF1F-46C808131DF8.jpeg

68AF9A51-ED44-4F0A-AFE5-3EDF02830EFE.jpeg

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I have more pix with more details.  I wish I had taken more  now I know more about them.   Fortunatly, my original build has some good ones.   Especially the pinion gear forward to the OD out put shaft.   Interesting how they made the short custom shaft to hook both together.

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Resetting / correcting the spedometer is simple.  I happen to have one of the guys down the road a few miles.   I told him what the GPS was reading vs the spedo.   He got out his ?40? Compartment  supply of gears and put it together.  I installrd it just before the original input.   Being pickey, I had him adjust it for zero difference  between  50  mph and 70 mph.  Below that its off  about 2 mph.   Over 70 mph I don’t care.  A rare speed to travel - only for passing.    

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2 hours ago, Jim Nelson said:

Resetting / correcting the spedometer is simple.  I happen to have one of the guys down the road a few miles.   I told him what the GPS was reading vs the spedo.   He got out his ?40? Compartment  supply of gears and put it together.  I installrd it just before the original input.   Being pickey, I had him adjust it for zero difference  between  50  mph and 70 mph.  Below that its off  about 2 mph.   Over 70 mph I don’t care.  A rare speed to travel - only for passing.    

 

 Jim, what do you mean original output?  Is it on the transmission OR after the OD?

 

  Ben

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Jim   Our speedometer problem was more involved.

 

First of all....  even though Lloyd left the speedometer and governor drive gears on the output shaft of the OD....these gears

    would spin freely on the shaft.  We had to pull the OD unit from our 1937 Special ......  then take it apart

     and then secure the two gears to the output shaft using LokTite   ( Lloyd's  suggestion )

     We were a little skeptical at first....but so far so good.

      ( maybe it was ThreadLock and not LokTite....but it was one of these type of products )

 

Secondly....Lloyd removed the speedometer and governor driven gears from the OD.   There has to be hundreds of different kinds

     of these little gears.   When you go to find the right  replacement gear...and you don't even know the original application

     ( and the nearest speedometer shop is several hundred miles away )  it can be a "character builder"  type 

      of problem to solve,    After about a month of research,  trial-and error  etc etc   I found that Studebaker

      5200XX series of driven gears would work (  mostly by dumb luck it turned out ).  It was an tip from

      Rick Larrick  of Fairbanks Alaska who put me onto the Studebaker angle

 

So now...after several months....we are happy.  We have the governor in again  so the OD operates in "semi automatic" mode just

      factory.   And the speedometer is working just fine  but it's off   about 6%.....this is because we needed   a 14 tooth  driven'  

      gear but the smallest gear tooth count in the 5200XX    series   is 15 tooth.  So i guess to get the 6%  error removed

       we'll have to install one of those  "speedometer correction adapters" ( I'm not sure what the correct term is.)

       We put one of these correction gadgets in our 1937 Cadillac when we switched from a 3.69 pig to a 3.07 pig....works great.

 

Jack Worstell       jlwmaster@aol.com

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Wow,  do you think it was worth it?   I was satisfied with the Lloyd’s modification as I’m one of those guys who subscribe to the “KISS “. principal.  It would have been nice if GM had just gone along and offered it as a option.   That brings the thought.   Is there a torque tube drive system  with OD that has a transmission that we could adapt to our bell housing?    The hot rod guys did lots of changes to get what they wanted in transmissions and engines they wanted.   Is there somebody who knows of a manufacturer such as Studebaker or Hudson that offered an OD option AND a torque tube drive train ?    That would put the OD right behind the transmission like they were designed to go.  They also might have better rear ratio’s.   Is’t this fun.  I love the challenges and ideas that we come up with.  

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Ben,  I used the original spedo output on the transmission  and bought one of those  ‘correcting’ gear boxes.  With the over drive, it’s only accurate when you are in over drive.  For me and our traffic, that mean’s I’m in over drive most of the time  as traffic is fast.  Nominally minimum of 45 in slow lanes and 60 + the rest of the time .  You have to keep up or get run over.  Thank goodness for over drive.   I bought a driving car,  one where I needed over drive as a starter. .  A “five footer” if you know what that is.   Looks great at 5’ but you would find little things as you get close to the car.  I love my coupe.....

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Here is the one I bought for my ‘38’.   Its hooked to the tranny’s output gear to show reference.

DD8D526A-678E-455B-80E9-67A895BCB578.jpeg

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 may need to get one of those for my '50. I changed gears from a 4.1 to a 3.36.  Third gear is right at 20 to slow.

 

  I would LIKE to have the overdrive. Finances won out.

 

  Thanks

  Ben

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Studebaker used an open drive shaft.

 

Why do you need the torque tube? I suppose the rear springs can be lighter because the torque tube prevents axle rotation rather than the springs.

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Which is why the question of ‘whose transmission could we use” to utilize a transmission that has the over drive  attached to it.   I would think there are some options out there.   The main premise iis “how can we keep out great pre war cars on the road”.   I know there will those who won’t do it because that is not the way it was built.   My thoughts were directed to using a drive system that is/was as close to the original, ie torque tube.  The first main issue is “what transmission can we use that has the OD attached to it”.   Then what drive train to follow.   Our leaf sproung rear ends would be the easiest.  ‘37’ and earlier would be the benefactors for our Buicks.   I’m just looking forward to keeping my cars on the road.

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Ben,  Keep saving as its the best option if you have one of the famous 4.44 rear ends.  3.6 or  3.4 becomes great options.  My ‘37’ has the 3.4 rear in the modified third member. .   But the flexability of the OD is great.   Of course, I’m  prejudice.   Nice to be able to run them side by side.  

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Yes we went to a lot of trouble.

 

But now our speedometer ( other than the 6% error which we will fix eventually) reads right no matter what mode we are driving in:

......direct drive without free wheel

 .....direct drive with free wheel

......overdrive ( 30% engine RPM reduction )

This is because the speedometer driven gear runs off of the OD output shaft....not off of the transmission output shaft

 

With the governor back in......we have in effect a semi-automatic transmission which is a convenient thing to have

 

Jack

 

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Very nice.   It make me wonder why Lloyd decided to go the way he did.   It might be the issue with trying to match the output to the spedo accuracy that you experienced.   Either way, over drive is the best way.   BTW, I owned a 1960 Austin Healey 3000 Mk I.   It came with electric actuated over drive.  Loved it.  I was a young pup in those days and did not realize what a neat car I had.  I did not give it a second thought how much the over drive effected its performance.  It just worked.     I’m sure you didn’t let those neat cars slip thru your fingers as  I did.  Mumble -  mumble - mumble.  What they are worth today.......

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I wonder if......

 

If you knew the source (original fitment) of the OD used in the conversion, one of their speedo drive gears should get it about right with the take-off at the back of the OD. The diff.ratio may be different and the wheel size may be different, but overall it can't be too different coz most engines of the era ran at roughly the same revs?

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12 hours ago, Jim Nelson said:

Is there somebody who knows of a manufacturer such as Studebaker or Hudson that offered an OD option AND a torque tube drive train ?    That would put the OD right behind the transmission like they were designed to go.  They also might have better rear ratio’s.   Is’t this fun.  I love the challenges and ideas that we come up with.  

 

Yes. Nash... and large-body Ramblers through 1966. There are some issues:

 

The torque tube is a whole different game in a Nash, the whole drivetrain is rigid except for a little rubber. It doesn't look to me like it would be that hard to adapt to me, but it is a completely different deal. There is no ball back there like a Buick or a Chevrolet or a Ford.  I read a posting on some other forum from a guy who had done it. He said it was much more work than he expected. Custom machining for sure.

 

Another problem arises if you need a mid 30s style floorshift. The three transmissions that commonly come stock with Borg Warner overdrive are Borg Warner T-86 (light duty), Borg Warner T-85 (heavy duty), and the Saginaw 3 speed. Of these only the T-86 even has a top cover, and it didn't come with both overdrive and a top shifter on the same transmission. It is possible to get a top shifter on one of these (jeep shifter IIRC), but you have to leave part of the side shift mechanism in and cut one of the old shift forks down to make the reverse lockout work for the overdrive. Some top shifters wont work because the overdrive case is in the way. There is more info about this on the Studerbaker Drivers Club forums. It is possible to make it work. It has been done. On the other hand if you have a column shifter, there are more options.

 

The third thing you are likely to run into is that the overdrive transmission is longer, and on many old cars there is an x-member or some important part of the frame in the way.

 

6 hours ago, Spinneyhill said:

Why do you need the torque tube? I suppose the rear springs can be lighter because the torque tube prevents axle rotation rather than the springs.

 

The torque tube also locates the axle fore/aft in a Buick. You have to add suspension members, usually ones from a Chevrolet truck to get rid of the torque tube.. People have done it successfully. I wouldn't. Chevrolets don't have that trouble, but the springs are not designed for the torque, and they are also pivoted/hinged at the axle tube. Something would have to change there. I wouldn't do that either. Fords have a transverse leaf spring and relied on the torque tube (and wishbone) to keep things from flopping around....


The trouble is right away you find yourself building a whole new car (whole drivetrain and suspension from the flywheel back).

 

I am building a higher-geared third member for my 36 Pontiac. I went with the ring and pinion change because it changes the car the least. It is expensive. It is not near done. I agree with Jim Nelson's assessment that overdrive is cheaper (at least at Lloyd's prices). If I could go back I would probably go that way.

 

There is one elephant in the room, however. You may need a third member rebuild anyway (it is more likely than you think). Then, you would have the third member cost on top of the overdrive . I have taken 3 rear axles apart within the last year (1936 Pontiac/Chevrolet). GM used ball bearings on the differential case back in the 30s. They weren't really up to the task. They used a Hyatt bearing on the pinion that, due to the design, has nothing to keep it located in the case. Buick axles are very similar in design, but larger. They also have a more powerful engine attached.

 

All 3 of these axles I tore down were working, but very close to catastrophic failure. 3 axles later I still don't have enough good parts to build my third member. I have a NORS ring and pinion (3.82 to replace 4.89) and NORS bearings (these old weird bearings are out of production and really expensive). I still do not have a good differential case to rivet my new ring gear to. If anyone has 35-36 Pontiac or 35-36 Chevrolet Master or 35-39 Chevrolet 1/2 ton rear axle parts laying around, feel free to PM me.

 

 

 

 

 

 

 

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1 hour ago, Bloo said:

Of these only the T-86 even has a top cover, and it didn't come with both overdrive and a top shifter on the same transmission.

My 1939 Studebaker has a floor shift plus overdrive. I suppose it might be unusual though because most cars had the column shift. IIRC the column shift box still had the floor shift nozzle on the top - remember the Stude gear box is on its side so the top cover is on the left hand side and it was easy to fit column shift kit to it and blank off the floor shift hole. Now that I look it up, it is a T88 box. 1940 went to the T86 and all column shift. The parts book is a mess because there were four options in 1939: gearbox with std or column shift, OD gearbox with column or floor shift. It is the changeover year. Some cars still had the 1938 T88 box (w/o OD) and the internals are different.

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