Buick guys: guidance please !

[Guest DeSoto Frank]

Would like some feedback about the 1939 Buick "Special" (39-40), 4-dr sedan.

What rear-end ratios were available in the Special for '39, and how are they out on the highway, cruising at 55-65 mph...

If they only came with stump-puller rears, are there later Buick rears (or ring & pinions) that can be swapped-in for better highway driving ?

What nasty "bugs" accompany Buicks of this vintage ?

The car I'm considering is a nice survivor, but as I like to drive my old iron, I'd like to know what I might be getting into.

Thanks for your help!

[The Old Guy]

The 39 -40 came with either a 4.10 or a 4.40 rear axle. There is a 3.9 that was available, but they are getting hard to find. They will run at 60-65 without any big problem, but the engine is singing to you. The one thing to watch is the early 39s had a short frame. They actually ended it over the rear axle, and that left the rear of the body just hanging. They had a recall and fix, so most were repaired, but it never hurts to check. they were also prone to heat if you ran them too hard on hot days.

Hope this helps

PS The rear ends did not change from 40 to 55 , but the 39 was by itself

[Guest DeSoto Frank]

Joe,

Thanks for your reply...if I opt for my buddy's '39 Special, it probably means gettiing rid of my '41 De Soto, and I wanted to get a sense of what "problems" might come with the Buick (beyond it being an un-restored 65 year-old car).

Along the same lines, how are the big Buicks from the same period - '39 -'40 ?

My Uncle Mike used to have a '40 Limited, and my Dad has some fond recollections of that car - wondering if it's Nostalgia or what...

[6219_Rules]

Frank, my mother's family had two big Buicks of that period, a 1938 and a 1940.

The 1938 sedan was the most handsome, but was, in her words, a dog on the road. It was underpowered or had something wrong with the engine that made it a liability. So they bought the 1940 sedan. It was far better, a wonderful road car, with no major problems aside from gas mileage during the war. I think the '38 suffered from being a bad apple because I have heard nothing horrible about others. And, in my humble opinion, the '38 was by far the nicer looking of the two cars. For what it is worth...just thought I'd add that to the mix.

[Centurion]

Frank, one of the BCA Board Members recently reviewed the entire Buick Club of America membership rosters to learn which model years are most extensively collected. Given trends in the collector car hobby, it is not surprising that the model years of the 1960's (especially) and 1950's dominated the top dozen model years collected. Nonetheless, both the 1940 and 1941 Buicks ranked among the top six model years of Buicks collected. These model years are very highly regarded among Buick collectors.

I have not had the good fortune to own one of these cars, but I know many owners of these cars who consider them to be excellent tour cars. In 1988, I followed a stock, original 1941 Buick Super from Seattle to Michigan. We cruised at 65-mph in the heat of summer all day long, and that '41's trouble-free performance was most impressive.

For my money, the 1940 Series 80 and Series 90 Limited cars are great buys. Recognized as classics by the CCCA, they are large, luxurious, and impressive, but remain relatively affordable. It was during this era that Cadillac complained bitterly to GM management that the Buicks were encroaching in Cadillac's territory. A close look at these cars reveals why Cadillac was concerned; these are stand-out cars.

[Matt Harwood]

The big Buicks are wonderful road cars. The '38 above was probably one of the smaller-engined Specials, which had a lot of weight to haul around with just 110 horsepower. But the 320 inch cars from 1936-41 are great highway cruisers and extremely reliable. I'm partial to the '41s, which I regard as the nadir of pre-war Buick styling and engineering, but that's just me.

I was also part of a crew who restored a '39 Roadmaster convertible sedan a few years ago, and when we were road testing it, we put a towel over the front grille and let it idle for a half-hour and it didn't overheat. Rebuilt properly, I don't think any of these Buicks will give you problems.

The small engine cars tend to have high numerical (low ratio) rear-end gears, some as high as 4.4:1 or more. While capable of cruising at modern speeds, they are typically happiest around town where the tall gears can get them moving pretty well. They'll run 55-60 all day, but I wouldn't push it much beyond that. The big engined cars had much more reasonable rear gears (my Century has 3.60s for instance), which, combined with the big motor, makes cruising at 80+ MPH a possibility.

Hope this helps. In my opinion, you can't go wrong with a '36-'41 Buick of any stripe.

[The Old Guy]

My 40 Super has taken my wife and I over 100,000 miles in the 32 years we have owned it. They are really great road cars, but I cheated a little and put the 3.42 axle from a 55 Century in my Super, and it just cruises at highway speeds.

[davenc]

My '36 Buick has a 3.90 rear end and at 60-65 mph, the engine is really humming. (Makes me uncomfortable to push it that hard.) Generally speaking I know to get the engine rpm down at those speeds, the rear ratio number needs to be less than the 3.9. But what ratio number should the target be and not be too low? Do you guys have a guideline or a general rule of thumb for this subject?

[Matt Harwood]

Well, first of all, you're limited by what is available. Like Joe said above, axles from later Buicks with lower gears can make a big difference. I don't think there are many gears for these old cars lower than the 3.42 that Joe mentioned. It wasn't until the gas crunch that gear ratios started dropping into the low 3s or even high 2s (both my '76 Eldorado and '93 Mustang came with 2.73 gears from the factory). Remember, when these old cars were built, there were no highways--it just wasn't necessary to build a car that could cruise all day at 75 MPH.

Your best bet would be to do a swap like Joe did, in which case you'll give up some around-town acceleration for better highway cruising. But if you don't do much highway driving, then leave the original gears in there--they'll help the car move with today's traffic.

Hope this helps.

[davenc]

Matt, I know I would be very limited on what I could do with the '36 rear ratio. I probably won't do anything to it anyway. I was just more interested in trying to understand what a reasonable target ratio would be. i.e. would dropping from the 3.9 down to a 3.6 make much difference or would it need to go down to the 3.42 range? I guess I'm looking for knowledgable opinions!

[The Old Guy]

The lowest ratio that is available on the 36 is a 3.9 That came in the 60 series. the 40 had : 4.44

80 : 4.2

90 : 4.55

At 75 MPH the RPM on each was:

40----3953

60----3426

80----3650

90----3777

It appears that you need either an overdrive or some BIG tires.

[Guest DeSoto Frank]

Thanks for the responses so far...

In the light of what I have read so far, for what my buddy is talking about for his '39 Special, I might just sit tight and look for a '37 or '38 big Buick...

[Mrbuick714]

I put a later rear axle gear set in my 51-51C,along with a near-new 263 engine. That car was right at home on interstates.Frank,listen to a really OLD guy.Get a 41 !

[Mrbuick714]

Sorry about the error,my car was a 41-51C.I still like any Buick,but the 40's and 41's art my favorites

[48LCCOUPE]

Dave, the diffenerce is relative. The big hit with anyone is overdrive which in a good case will be a .7 reduction. Apply that to a 3.90:1 ratio and you end up with a modern and comfortable 2.73 ratio at cruising speeds in overdive.

To apply this to an individual situation, if your engine was humming at 3500 rpm at 55 mph with the 3.90 ratio, the above overdive would drop rpm's to 2450 or .7 X 3500.

Whereas a change from 3.90 to 3.42 with the above would reduce engine rpm's from 3500 to 3045 (I think, doing this on paper, can't find my calculator) or 3500 X .87. 455 rpm is not much of a reduction. 3.9 to 3.6 probably wouldn't be worth the effort.

Remember, I haven't a clue as to the rpm and speed, just picked out some numbers for comparison. Divide smaller # by bigger ie 342 divided by 390 12% decrease ( .876 ) not much. 2.73 divided by 3.90 30% decrease YEE-HAW!!!

[Guest Skyking]

I recently rented Seabiscut with Jeff Bridges. In the movie he owns a Buick dealership and drives a beautiful 38'. Alot of beautiful cars and a great movie! ...........