'67 Monaco, how to replace transmission mount, question about u-joints

MoPar~Man

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Unless there's some trick about making enough room to get the old mount out and put the new one in, I'm stumped for now. I've removed the 2 bolts holding the mount to the trans, and the single nut holding the mount to the frame cross member, have jacked up the trans until it's making contact with the underside of the floor, the old mount (which is quite beat up but hasn't separated) is loose and I can move it around but can't find any angle to extract it. It's somewhat spongy and has some give, but the new one is rock solid and would be even harder to put in:

mount-1.jpg


mount-2.jpg


The mount must drop into a channel in the cross member and why they made that channel so deep, I don't know. It's a real pain. Even if I had an extra 1/4 inch that would be enough to slide the new mount in but that stupid bolt sticking up would be the next problem.

The way I see it, the only way to do this is to also disconnect one or both engine mounts and lift the engine and trans simultaneously, and that *might* work.

Alternatively, I cut the bolt off and drill and tap a hole on the other side (the other plate) and fasten that side to the crossmember with a bolt.

Has anyone else had to deal with this?

Regarding the U-joints, I thought I could unbolt the half-circle hold-down plates and remove the 2 joints, but that's only partially possible on the rear joint. How exactly do you remove the joints? They look pressed in.
 
Remove cross member?

Pull the whole driveline out typically once the rear straps are undone

Watch for fluid coming out the back of the trans, prepare.






How exactly do you remove the joints? They look pressed in.

It's a bench job, some people finesse the cups out in a vice with receptor cups and drivers, but with most trashed U joints it's done with a BFH, preferably of the "cross-peen" variety, and do not hit the tube, ever.

This is the hammer I used in a shop, as recommended by my boss - at a driveline shop - to buy.


Screen Shot 2022-10-08 at 1.57.52 PM.png
 
Unless there's some trick about making enough room to get the old mount out and put the new one in, I'm stumped for now. I've removed the 2 bolts holding the mount to the trans, and the single nut holding the mount to the frame cross member, have jacked up the trans until it's making contact with the underside of the floor, the old mount (which is quite beat up but hasn't separated) is loose and I can move it around but can't find any angle to extract it. It's somewhat spongy and has some give, but the new one is rock solid and would be even harder to put in:

View attachment 561956

View attachment 561957

The mount must drop into a channel in the cross member and why they made that channel so deep, I don't know. It's a real pain. Even if I had an extra 1/4 inch that would be enough to slide the new mount in but that stupid bolt sticking up would be the next problem.

The way I see it, the only way to do this is to also disconnect one or both engine mounts and lift the engine and trans simultaneously, and that *might* work.

Alternatively, I cut the bolt off and drill and tap a hole on the other side (the other plate) and fasten that side to the crossmember with a bolt.

Has anyone else had to deal with this?

Regarding the U-joints, I thought I could unbolt the half-circle hold-down plates and remove the 2 joints, but that's only partially possible on the rear joint. How exactly do you remove the joints? They look pressed in.
I agree with dropping the trans x-member to replace the trans mount

I use a vise with a wide socket to receive the u-joint bearing cap and a nut or narrow socket to push the cap into the receiving socket. If the cap sticks during removal, a rap on the vise with a hammer usually frees up movement. Flip the wide socket for install.
20190524_170327.jpg
 
Pulling X member is [thoretically] easy.

Support the trans appropriately, the pan is strong enough to support it, a big piece of flat wood on a jack, you're not trying to lift it, just keep in in place while removing X member, 4 bolts/nuts typically.

Eat your Wheaties like they used to say back in the day, use impact at your own risk, do no harm.

If you see heavy rust on the fasteners, use plenty of spray and patience, otherwise Mopar bolts are quite strong.

Use sockets and wrenches that fit well, this is no time for cheap tools.
 
I'm not going to touch the cross member. No idea how many tons of torque the torsion bars are putting on it, one side of this rail where it connects to the rocker panel is not in good shape.

I assume you have to remove the retaining clips before pushing the cups out? I'm trying to imagine the reverse procedure to install the new ones.

When pulling the shaft out of the transmission, I assume it will just slide out?

When I bought the trans mount from rock auto, I ordered some wheel bearings and u-joints. I wasn't paying attention or I didn't do enough research to realize that there seems to be 2 different size cups. I bought 2 different joints (just out of curiosity to see why they were different - rock was offering like 6 different joints) and it just turned out that the 2 I ordered have different cup sizes.
 
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I'm not going to touch the cross member. No idea how many tons of torque the torsion bars are putting on it, one side of this rail where it connects to the rocker panel is not in good shape.

I assume you have to remove the retaining clips before pushing the cups out? I'm trying to imagine the reverse procedure to install the new ones.

When pulling the shaft out of the transmission, I assume it will just slide out?

When I bought the trans mount from rock auto, I ordered some wheel bearings and u-joints. I wasn't paying attention or I didn't do enough research to realize that there seems to be 2 different size cups. I bought 2 different joints (just out of curiosity to see why they were different - rock was offering like 6 different joints) and it just turned out that the 2 I ordered have different cup sizes.
Trans Cross Member & Torsion Bar Tension
I usually put the front in the air, measure the distance from the bolt head to the torsion bar tensioner, then loosen both bolts to remove all tension. Reinstall at same height when done with trans cross member.

Trans cross member R&R is easy with no tension on the torsion bars. Otherwise, you can have a problem lining up the trans cross member bolt holes (true by experience for all fuselage years of c-body)
 
I had a totally EASY time with my tranny mount, but this came of pulling the entire engine and transmission as a unit, and dropping another in the same way. I recall the tranny shop guys even whined about the mount when I commissioned them some years ago.

I believe the only way to do the job would be to remove the crossmember, which is the proper way to do it anyhow. Thus is it specified in the 1966 FSM:
1665360846213.png

With that crossmember loose, you shouldn't have any further hassle. Or, pull the whole works as I did. I still think that's about the easiest way to get anything serious done to any part of the powertrain. Of course, the slab side cars are easy in general. Good luck!
 
Remove cross member?

Pull the whole driveline out typically once the rear straps are undone

Watch for fluid coming out the back of the trans, prepare.


It's a bench job, some people finesse the cups out in a vice with receptor cups and drivers, but with most trashed U joints it's done with a BFH, preferably of the "cross-peen" variety, and do not hit the tube, ever.

This is the hammer I used in a shop, as recommended by my boss - at a driveline shop - to buy.

That's a SERIOUS WHACKER bro! I say, use a brass drift to tap those out. Again, I've ALWAYS had an EASY time with this stuff, so my advice may be worthless here.
 
I've never had any issues dropping the X member on ether a C or a B body, but I've never worked on a non California car, no underside rust.
pop the 10 bolts (yes there are 10) and replace the mount.
 
My old mount wasn't too bad to get out...it fell apart. Getting the new one in was an experience. I ended up grinding some of the bolt off and grinding more of an angle on the back part of the rubber so that it could "tip" in. Even sprayed it will oil. With my helper guiding it...I coaxed it in with mix of swearing and extreme violence. This is one of those parts that I consider BTF (Beat to fit.)
 
My old mount wasn't too bad to get out...it fell apart. Getting the new one in was an experience. I ended up grinding some of the bolt off and grinding more of an angle on the back part of the rubber so that it could "tip" in. Even sprayed it will oil. With my helper guiding it...I coaxed it in with mix of swearing and extreme violence. This is one of those parts that I consider BTF (Beat to fit.)
I believe the original poster's car is 1967 or 1968 Dodge. What YMM is yours?
 
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