The Stovebolt Site Forums The Shop Area Engine Shop 3 speed overdrive crossmember

The Borg-Warner 3 spd overdrive that I bought has a pad cast on the tailshaft housing that is drilled and taped for a crossmember. It came out of a '62 Chevy car. Does it need its own crossmember (couldn't hurt could it?) and will the automatic transmission crossmember out of a 73-87 C-10 fit it? My frame is drilled for a crossmember in the location that it would be in already. I know that I would have to get an automatic transmission mounting pad for it also.

no it doesn't need it in the truck - yes it could hurt if you have a third mounting point, the trans cross member is only used w/ the automatic, which doesn't have the bellhousing mount

Bill

Ok, did the trucks not come with a crossmember when it was optioned in the factory? And how would it hurt to have it there since the R10 weighs a good bit more than my regular 3-speed and is about 10" longer?

You don't want more than three mount points for an engine/transmission combo, or it will bend/break things when you put it under load or drive over bumps.

and no, trucks never had crossmembers with any standard trans - not sure why it's 10" lomger, the OD from 55-68 is a direct boltin replacement for the standard 3spd 55-68, if it were longer it'd take a different driveshaft

Bill

When I picked it up, it just seemed longer because of the overdrive unit. It could have been my eyes playing tricks on me again. And only having 3 mounting points makes sense. Thanks guys.

I believe most years of the 60's trucks (and cars)had the short tailshaft for the original 3 speed. The OD trans is the same length as the ones used in the TF trucks. You will need to modify your 66 driveshaft for this install but it doesn't need a rear mount.
Fred

Fred - I have 68 3spd's in both my 57 and 58, bolted right in [except for the output spline difference], never heard there was a different trans between 55 and 68

Bill

Bill, what kind of modifications did you have to make to get the trans to work? The one that I have has no shift arms (I was thinking of using the arms on my standard 3-spd) but it has the wiring harness on it. What did you do for the o/d shift cable, were there any modifications to the shift linkages, and how did you wire it up? I would like to get a toggle switch with a light in it from my FLAPS and mount it on the dash under my heater control knob. Would that work?

A toggle will work, but add a relay of some sort to carry the lod going to the solenoid. I used a headlamp relay, BlueStreak part #LR32. For the cable, I used a Chelsea PTO cable. Much heavier that the standard type cable, and smoother actuation. Also, you should be able to just use the original shift arms from the factory tranny to hhok it up.

Awesome, thanks guys. Dad and I are trying to get all the technical stuff sorted out before we dive into this since this is our first trans swap. Next question: is there a way to test if the solenoid works? The guy I bought it from said that it worked, but I'd like to check it myself.

apply power to terminal #6 on the solenoid. It should klunk in with some authority. May need to clean the solenoid off to see the markings, though.

My pa in-law has a 55 Ford Customline with that trans. It has a T-handle mounted under the dash and it even has "overdrive" embossed in it. It's still available through vendors if you want something to look proper,
Scott

I was thinking of welding a piece of metal rod onto the pull cable and mount that under the dash where it would have been originally.

There is no real benefit to a trans mount, but it wouldn't be any problem as long as you use a rubber mount, extra strong is not a problem. There is negligable flex in these frames between the bell housing and the rear of the trans.

Dad asked me this one: since we don't know what gearing the donor car had, will the speedo gear I have now swap over to the o/d trans?

Bill,
There is no difference in length of the 55-68 OD transmission. What I was refering to is the standard 3 speed non OD trans in 60's (through 67)trucks is about 5" shorter than the OD trans. 68 & up Saginaw non OD 3 speeds also have the long tail housing.
Fred

The speedo gears will not swap. The internal gear on the output shaft is a different size. Most likely, the car the trans came from had 4.10 gears and 14" tires. This will make your speedo read slow compared to actual speed. Consider checking with a speedo shop for an adapter to correct the reading. Or if you have a tach, you can judge speed off the rpm, just like they do in Nascar.

I'm going home from college for the summer tomorrow. When I get there, I'm going to add some pictures of this thing to my webshots album. Thanks for your help.

Ok, I just updated my webshots album with the pictures of my transmission.

Bill, my trans looks nothing like yours does. It is 21 and 3/4 inches from the mounting face to the yoke seal and the input shaft is 6 and 5/8 inches in length. I'll crawl under my truck tomorrow and measure my original trans, the o/d is definitely longer than the original one.

Here is the pad I mentioned.