VCCA Home Forums TECHNICAL - GENERAL Mechanical - Engine, Trans, etc Gear Ratio ?

Trying to find if a 3.08 ring & pinion will fit my in my stock 56 bel-air ? I get a little confused with all the numbers. 10 bolt 12 bolt 8.5/8.6 ? Any help along these lines would be greatly appreciated.........

The 1960-1964 cras used the 3.08 in some engine/transmission combinations. The complete "pumpkin" will fit in a 1956 although it is a bit beefier in places.The 3.08 was used in 1960-1961 283 with PowerGlide (not Turboglide), 1963-1964 Biscayne and BelAir sticks and Power Glide with 283 engine as well as the 6 cylinder models. Wagons and convertibles didnot use it. The 283 with a 4 Bbl. did not use it. Also used in 1959-1961 348's with Power Glide or Turboglide.

I hope this isn't viewed as "high jacking," but my (modified) '51 Chev wagon is said to have a '57 Chev rear-end with 3.08's. I guess Gene's above answer explains how that would be possible??? Confirmation???

Thanks,

Bill.

Thanks Guys, I've also been checking and from what I can find out. 1. The 3.08 gear came out in 1959 and ran through 1964.
2. The ring and pinion will not interchange, It seems
the 56 has a thiner gear,
3. Their seems to be two solutions here, one is to swap
the whole rear end for the later model, or find the
correct pumpkin. From what I can see they run about
$ 700.00 to $ 1000.00 for a used one.
Might have to stick to what I have, That is a lot of

Yes, the complete center section would have to be exchanged. This eleminates the extra cost of have the gears only changed and set up properly.
I used to change the center section in my '57 in less than an hour.
If your 1956 is a stick it willl have 3.70 gears. If a P.G. 3.55 gears. The 3.08 is quite a tall ratio for a 265 PG with 15" wheels.
Another choice would be a 3.36 for a stick.
Cars with the 3.08 all hd 14" wheels.

Thanks Gene, Your information is 2nd to none. the engine and transmission in the car is a combo 350/350. From what I can find out there are no ( NEW ) gears that will fit, The newer gears are thicker than the original ones. I'll pass the word to all my friends to keep an I out for one at the right price ?

With a 350/350 a 3.08 would be a great choice.

I can't remember. Is the 350 transmission the one with the OD or is it the 400?
Charlie

Charlie, I think the 200R and the 400R are both O.D. Transmissions. The 350 is not........

Neither the TH350 or TH400 are overdrive transmissions...Joe

Buy the way Gene ! I got a 37 floor shift transmission for my 39. Swapped out the two top plate covers and everything went very smooth almost. I dropped the (slider bar) as I call it into the tranny, The good part is I have a long magnet and retrieved it. The worst, and longest time I spent was removing the cotter pins from the linkage ( NO ROOM TO WORK ) The most stressful was the measurements for cutting the hole in the floor for the shift leaver, After making a bunch of templates measuring countless times I made my cut ? To make a short story long. Everything came out perfect ! Everything is working very smooth and as they say in the old days ( LOOKIN - GOOD )

MERRY CHRISTMAS TO YA'LL

Hi p.k.,

Happy holidays to you also.

Somehow I missed following this thread. I agree that the 3.08 ratio will be great with that 350/350 combination. What size tires are you running?

Your note about the floor shift conversion on your ”˜39 caught my eye. Did you have the convoluted column shift set-up on the car? If so, I can see why you were frustrated. I saw one during a visit with Bruce Bugay. He had it in his extensive collection of parts. What a Rube Goldberg contraption! I would be surprised if you were able to find a gear half the time.

Take care and enjoy the holidays.

I am putting a 1954 manual transmission with 3:70 gear ratio on my 1948 sedan with a '61 235 engine. Will I have to change the speedomoeter cable with the '54 transmission?

What rear axle are you using? The standard axle in 1948 was a 4.11. There was an optional 3.73 ratio.

I assume that you mean changing speedometer driven gear.

The car has the original 4:11 rear end. I was given a transmission and rear end from a 1954 Bel Air, the manual with 3:70 gear ratio. Am aiming for a better ride than the 4:11 provides when touring and hopefully better gas mileage.

Yes on the speedometer gear.

We need to let some experts jump in on this. It might not be as simple as changing just the driven gear. You might need to change the driving gear also. Both gears have to be compatible.

The "easy" solution is to find a '54 speedometer cable and determine that the driven gear will fit on the end of your '48 cable. That will give you the correct speedometer cable speed.

The tricky part is that there is a chance that the '48 driven gear is not compatible with the '54 driving gear. So one of them would get chewed up pretty quickly.

The drive gear is pressed onto the rear U joint yoke, so use the 1954 U joint and drive gear and torque tube as it is large and improved (if the bushings are OK).

Do not use the 1954 transmission as it is a different length.

Rusty37, Chev Nut..thanks for the information!