Borg Warner T-35 (probably shot)

New here. First post and it's a doozie.
I have a 3 speed auto T-35 in a 71 DJ-5 (AM General postal jeep). Unfortunately, reverse is the only thing I've got going right now. I'm assuming there is damage/wear in the tranny that's preventing it form engaging in drive, but is it possible that I'm looking at anything that won't require a full swap or rebuild? Fluid is good, although since it stopped engaging, there has been a leak between the bell housing and flex plate(?) - the question mark is because I know little about transmissions beyond the theory of how they work. If I wanted to swap in another T-35, are they all identical, or did they alter bolt pattern by year and model? Do they all have the same tail length (important, since a DJ has an 81" wheel base). I can't imagine there are too many tranny shops that are well versed in a 45 year old model, but even if there are, will machined parts be available if it's a munched clutch pack, broken pump or similar? I guess the real question is, how bad of shape am I likely in?

Try these guys, might be some help>>>>>> http://www.postaljeep.net/contact.htm

You may want to reach out to Dan Curtis (amx39068). He's also in Phoenix and probably knows who to take it to for tranny work. I'd just leave it sit and not try to drive it. Hard parts (like drums) are getting hard to find for the Borg Warner trannies. Gaskets, bands, and friction plates are no problem to get. The torque converter will need to be rebuilt since they are not available new.

More than likely it isn't just shot. The first thing I'd do is disconnect the shifter linkage and get under the Jeep and put the trans in L (lever on trans all the way to the rear). Jack up the rear axle and put it on jack stands, and block the front wheels. You will have to bypass the neutral safety switch (pull the wires and connect together, IIRC). Then start the engine and see if the wheels turn. If so bump the lever forward one to the next detent. That should be D1, and the trans should shift. If it does the linkage is the problem, not the trans.

If that test fails, drop the pan. Look at the tubes first. Make sure they are all in the right place. You may need a TSM to locate them and determine where they should be, but if they are loose it should be obvious. Check the servos. There is a link between the front servo and the end of the band, make sure that's in place and the servos engage the bands. You may want to check the band adjustment. If all that looks good, you need to pull the valve body. It should be disassembled and thoroughly cleaned. Most of the time a problem like this is simply due to a sticking valve or clogged passage in the valve body.

Yours should be an M-4x, not a M-35. The 35 has a TV cable, the 4x has a vacuum modulator and an electric kick-down. Make sure you have a good vacuum line on the modulator. You may want to try a new modulator, but I'd clean the valve body first. If it has a cable from the trans to throttle linkage make sure the cable moves easily and is connected. If the cable wasn't connected you probably do have a fried trans. A bad vacuum modulator could do the same.

3213867is a 72-74 199/232 block casting number. I don't have manifold casting numbers. You can get the head casting number after removing the valve cover.

There is a number on the trans tag that will have "AS2-40" or something like that -- the last two numbers are the trans model number (in the example a M-40, the AS2 really doesn't matter, can be different). That number is screen printed in the lower left of the hex shaped tag.

All of those trannys are basically the same, the only external differences are the M-35 has the TV cable, the later models use a vacuum modulator and an electric kick-down solenoid. They also have provisions for a trans fluid cooler or air cooling, depends on the bell housing and torque converter used. The power holding differences include things like a different number of clutches and steels, and sometimes different hardness shafts, but the rebuild sequence is the same on all.