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3spd OD, shifter, and rear end

1K views 5 replies 3 participants last post by  f.i.57chevynut 
#1 ·
I picked up a parts car that has a 283/3spd OD combination and I'm woefully ignorant of transmission, and rear axles.

I'm guessing the transmission, given the sad state of the rest of the car, will need to be rebuilt. I was wondering if there was a ballpark estimate of how much a rebuild would cost? (as opposed to a new 5spd, or auto install)

Would a floor shifter be the same as a standard 3spd? (I want to get away from column shift)

I've read that the 3spd OD transmissions were typically mated with a 4:11 rear end, if it is a 4:11, is this a piece worth salvaging, or swapping to go underneath my wagon before the donor car is put to rest? I understand that stock rears aren't terribly strong, but for the time being I'm just looking to get it back on the street, rather than light the tarmac with it. However, I don't want to measure off the line acceleration with a calender. I also haven't taken the time yet, to identify the current rear end under my wagon.
 
#2 ·
Since you said 283 I assume it's a 57. 55 to 58 had 4.11's with OD. 59 and later had 3.70's. Make sure you get all the wiring, kickdown switch and mounting bracket, relay, and cable.
The trans should be driven to see if it shifts OK and doesn't jump out of gear in second when letting off the gas and jumping out of third under power.
The column shift is the same. The overdrive shifts easier than a standard because it freewheels ( so the rearend doesn't drive the gears unless the OD is engaged). I still use the column shift in both my wagons and the convertible. I have my overdrive wired so I can shift it in and out with a switch on the column shifter. I have 6 speeds instead of 3, and the spread between gears feels just like a close ratio 4 speed.(plus 2 more).
Definitely save the rearend no matter what it is. The final drive ratio wit 4.11's in overdrive is 2.87, great for the highway. If your engine is good and well tuned you should get close to 25 mpg.( if you keep the speed down to 65 or 70.)
As far as strength, the ring gear is the same 8.2 as the early Camaro and 64-72 Chevelle and lower horsepower Impalas. The bearings are bigger in the 55-64 rearend than in the other 8.2 rears and the axle bearings are replaceable and don't use the axle as the load bearing surface so if the bearing goes away it doesn't ruin the axle. And no c-clips to worry about if you like going around corners fast.
As far as cost on rebuilding the trans, it can vary widely depending on what is needed. Synchros are pricey these days. I used to like to find old 3 speeds that were grannied around (usually 6 cylinder cars) and take all the gears out to use in my overdrives.
 
#3 ·
Thanks for the advice, much appreciated. I've opted for an Ididit "floor shift" column, as I'm still undecided if I want to go with this 3sp OD, or toss in a 700R4. Whichever I choose will be behind a mild 265 to start with. I've got a couple of 3spds in the garage, but I know little about them. I'll have to research them to see what they are, and if they'd be worth hanging onto for donor parts.
 
#4 · (Edited)
I picked up a parts car that has a 283/3spd OD combination and I'm woefully ignorant of transmission, and rear axles.

I'm guessing the transmission, given the sad state of the rest of the car, will need to be rebuilt. I was wondering if there was a ballpark estimate of how much a rebuild would cost? (as opposed to a new 5spd, or auto install)

Would a floor shifter be the same as a standard 3spd? (I want to get away from column shift)

I've read that the 3spd OD transmissions were typically mated with a 4:11 rear end, if it is a 4:11, is this a piece worth salvaging, or swapping to go underneath my wagon before the donor car is put to rest? I understand that stock rears aren't terribly strong, but for the time being I'm just looking to get it back on the street, rather than light the tarmac with it. However, I don't want to measure off the line acceleration with a calender. I also haven't taken the time yet, to identify the current rear end under my wagon.
To add to what Tom said, The shifter is the same, but the shifter brackets are different for a hurst shifter for a 3 speed OD, (to clear the solenoid) They generally use a hurst mystery shifter or master shifter, but a 3 speed competition shifter will also work. About the only one that will not work is a INDY.

Pops or I have patterns for the brackets if you can't find a set.

I just sold a set to Sierra Gold, I think I have most of one other set left.

I think the 3 speed OD is way cooler than a automatic OD trans. Sort of a semi-automatic. You only have to step on the clutch when at a full stop and you just shift the lever from first to third. The OD does the rest. My car has a 3.70 rear end, which I think is just about perfect for a OD car. Not as quick off the line as a 4.11, but good. At 70 mph I am showing 2000 rpm with 28 inch tires.

If your inner fender relay is shot, (which they often are) and you don't want to spend the 150 bucks they ask for a new one. Radio shack has a relay that works great, and is $6.49.

http://www.radioshack.com/12vdc-40a-spst-automotive-relay/2750001.html#.VJW-2sAKA

Here is an article that explains things well. Its written for a ford but all Borg warner OD's are the same.

http://www.fordification.com/tech/overdrive.htm
 
#5 ·
Reference rebuilding the tranny. IF there is something wrong with the transmission part, the BW tailshaft will fit in a regular stock (muncie) transmission, so if you have a good 3 speed, it is switchable. The only hard part to find for the BW is the sun gears, if yours are ok then the rest is not hard to find.
 
#6 ·
The 700R, being an automatic with a front pump, uses horsepower just to make the transmission work. With a small engine the percentage of power that the trans uses is greater than with a larger engine. The stick overdrive doesn't have a horsepower robbing front pump, so better gas mileage.
 
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