Transmission/Transfer case mount

[Jetsetr]

Ok Braintrust...here’s today’s issue!

Noticed excessive vibration/movement in transmission under load. Was hoping to find a broken engine/transmission mounts...

Instead found a trans to mounting plate issue...

Mount was loose, but it DOES NOT line up properly with the rear transmission-transfer case skid plate mount...

Previous owner was only using 1 bolt in the mount. Wondering if it’s the wrong transmission skid plate mount....

Unless I redrill the mounting holes in the skid plate there’s no way it’s going to work...(that is an option)...maybe I’m missing something obvious (and the skid plate does only go in one way, I checked!!).

Driveline seems to be lined up properly (would have to be several inches off to line up with the current skid plate mount).

P.O. really had no idea what he was doing on this, and obviously wasn’t a very good mechanic...

Ideas, suggestions, pictures??

Thanks in advance...
Dave

 

[Lumpy Grits]

Pictures really are needed here.
LG

 

[Jetsetr]

Working on pic...

 

[Jetsetr]

Working on pic...

 

[Jetsetr]

Ok...what we are looking at is the transfer case skid plate and mount, from the right rear. You can see the exhaust pipe running down the left side.
The transmission mount is sitting on the skid plate where it was bolted down. You can also plainly see where the mount is SUPPOSED TO bolt to the transfer case, and how far off it is. P.O. only had one bolt in and everything was loose, including the actual transmission to bell housing bolts....thus causing the movement and vibration....

 

[Lumpy Grits]

Loosen up the engine mounts some-and see if using a chain and turnbuckle you can 'guide' the mount to the correct location.
LG

 

[Jetsetr]

LG...moving the trans and driveline wasn’t feasible...
Everything was pretty much aligned properly- driveshafts, shift rods out of trans.
Ended up re-drilling new mounting holes in the skid plate. That worked...
Still had a vibration in it and started looking at the driveline hard. Rear u joint on diff had a loose cap and u joint was moving. All squared away now... thanks for the reply’s though...
Dave

 

[Lumpy Grits]

You did good!
Might not hurt to replace the other U-joint.
LG

 

[Jetsetr]

LG...yeah, both rear driveshaft u joints are going to be replaced...front rear u joint doesn’t look like it’s been greased in about 50 years. P.O. put 33’s on it and it really increased the pinion/transfer case angles...if I was going to do serious off trail driving or upping the horsepower with this I see that being an issue...no popping the clutch in 4 low! weak link for sure...but just going to two track it in northern Michigan and be nice to it...I hate walking out of the woods.

 

[Lumpy Grits]

You really NEED to get that Jeep to a front end shop for an alignment printout.
Bet with the lift messed with the camber, caster and Toe-in settings.
Shims on the axle spring pads, will correct the pinion angles.
LG

 

[Jetsetr]

That’s a great idea on the shims... the front diff is fine the rear DS angle is really steep. I know on my semi motorhome we added 3 driveshafts when we stretched the frame...in that application Spicer wanted no more than 3 degrees pinion angle. A wee bit more torque (1800ft Lbs) in the 12.7 Detroit.

It actually drives very well, has Rough Country shocks and steering stabilizer.
Kinda wish it didn’t have power steering it’s awful sensitive above 50. No highway speeds for me, it rides too rough with the short wheelbase. It’s happy below 55 and I have no reason to go any faster. Needs a LOT more gearing with the taller tires. 5:13 would be great if the fit in the housings. High 4’s (4:88) would work better than the 2.90 it has now...

Only paid $2,700 for it and have about $500 more in upgraded/new parts. I knew it needed some TLC. Has 70K original miles and from Georgia originally.
It’s really easy to work on and a ton of fun...

 

[Lumpy Grits]

Get that frontend into spec. It will handle 'mo-better'.
You want your caster 6-7*.
Toe in total, 1/8-3/16".
LG