Transmission replacement

[2305johnt]

Hi everyone

Apologies, another daft question.

Our 1943 GPW has had the original gearbox changed. I think T90? This runs well but sticks up through the floor. We are renovating the jeep and we have now got to the stage of wondering what to do.

I realise its hard to do but could I get opinions on what modifications are needed to change back to an original gearbox? Money is an issue as original ones are very hard to get in the Uk

Thanks

[Wolfman]

T-90 case is 1 inch longer than a T-84.
Beside the T-84 , you would need a shorter T-84 clutch release cable. Rear transmission mount and a shorter front and longer rear drives shafts. The T-case will be 1 inch farther forward.

[dpcd67]

And move the cross member back where it originally was since they likely moved it to hold the T90.

[Adam]

Clutch z bar may have to come back forward as that went back as the transfer case moved back. also the pedal to z bar link may be different. check the drive shaft length against known dimensions, some folks just use the same shafts as far as the front goes, and they will cut the spline area on the rear one to get a little extra room. Now did they move the tranny back or move the engine forward? T-90 is 1.250" longer, case size, dont know if the bottom mounts are that much further back. also t-90 uses a deeper drop crossmember, or they could of put spacers between the member and its mount. Floor may of been cut or original tranny floor cover may be gone too. Lot of stuff, but not that big a deal.

adam

[2305johnt]

Thanks for the replies - most useful.

We have found a gearbox - we were told its was 'WW2' but we are not sure if its T84?

We are told that It is stamped :
T84J-1A
W DIV 2

Can anybody tell me if this might be a correct gearbox for the 1943 jeep?

Thanks

[Adam]

How about the transfer case? what is its intermediat gear shaft size, if other then 3/4" it will not bolt to the tranny due to interfearance at the shift interlock area.

Adam

[bazza46]

T84- J is definitely a T-84 case.

[2305johnt]

Hi again

More help needed on the transmission issue please.

We have found a T84 gearbox and transfer but would this fit into the existing CJ 1950s engine?

Thanks

[Bruce W]

Now we get a peek into a can that could be full of worms.
A 1950’s engine, assuming it’s still a flathead, will almost certainly be a CJ3A engine. Not a problem in itself, but what else goes with it? The T-84 will not work with a CJ3A bellhousing. A CJ3A starter will not work with a G503 bellhousing. A G503 starter will not work with a CJ3A flywheel ring gear.
You’re going to need to know what you’ve got so you’ll know what you’re getting in to.
BW

[2305johnt]

Hi Bruce

Thanks for the answer!!

We did suspect this so we are back to square one.

Sorry for another quick question but are there are any T84 parts - casing or anything - that would help with the issue of the T90 protruding from the floor?

Thanks

['42 Peep's Motorpool]

Sorry for another quick question but are there are any T84 parts - casing or anything - that would help with the issue of the T90 protruding from the floor?

Thanks

Hi,

As Bruce said, it's going to depend on what you have, and what you plan on using. If you are using parts that are all directly interchangeable, it should 'solve' the problem. However a lot of these T-90 conversions weren't well done, and more often than not the people doing them 'buggered' up more and more just to get it to fit and function. I've seen engines moved forward, or intermediate crossmembers moved backward, I've seen engines sitting higher than stock (raising the position of the bellhousing for example, directly affecting the transmission), and I've seen a lot of floors hacked to pieces to make all that 'fit'. If you are lucky, the crossmember was not moved, or if it was, the engine mounts were not messed up.

It might be easiest to post photos of what you have?

[2305johnt]

Thanks for the replies, for now we will stick with the T90 so that we can run the jeep around to see how the engine etc goes. Then maybe change to Y84 later

[2305johnt]

Hi

we are now nearly finished with the renovation but we are desperate for a throttle link plate - the part that fits on the engine. There is nowhere in the UK that has them so we are stuck. At the moment it is a credit DIY job with a large stretched spring !! Has anybody got any ideas where I can source this from?

Thanks

[Nigel]

Do you mean the plate that bolts on the back of the engine?
If so Jeepsudest in France have them.

[2305johnt]

Thanks for the help, will try them. I don’t suppose you can direct me to the correct part number and/or description?