e-Brake drum rubbing on Crossmember (1 Viewer)

[rstoddard]

I recently had to pull my TC (and Tranny) to have it rebuilt. For reasons I won't go into, I had to do it by dropping the engine (i.e., removing the lower motor mounts and pulling the bolts off the top motor mounts, and lowering the transmission and securing it). This worked reasonably well, except that the engine didn't drop exactly evenly. The Starter prevented the engine from dropping very far on the right side so most of the drop (which wasn't that much) seemed to be on the left side. In any event, it was enough to drop the TC low enough to pull it out from under the Crossmember. NOTE: I have a SM420 Transmission and a 5" Advanced Adapter (AA) adapter between the tranny and TC. That pushes my TC and e-brake right up to the crossmember. There was only about 2" of clearance- just enough to allow me to pull the TC off the Transmission.

I managed to get the TC back on and everything reinstalled, BUT HERE''S THE PROBLEM:

After all of this, the alignment of the engine, transmission and TC has been (apparently) slightly altered by taking this approach. I was test driving today and I started hearing a loud screech sound of metal grinding. OH LORD! Upon inspection I noticed that the Brake Drum has shifted to the right slightly such that it is no longer centered under that crossmember hump, and it is now up against the right side of the crossmember. Holy crap!

So, the problem (and the solution is obvious): I have to get the Transmission/TC/e-brake straightened (shifted left) so that it is more centered under that hump in the crossmember.

My problem is, I'm just not that sure what is the best way to go about it. There really can't be very much play in those motor mounts. I had a really hard time getting the front (top) motor mounts to line up the first time, and I'm a little concerned about trying to move all that weight from below with jacks and levers. It seems that would be (potentially) putting a lot of stress on the engine mounts. I guess there might be more flexibility in adjusting the rear (lower) engine mounts (and just loosening the top bolts slightly), if that could be sufficient to shift things into alignment.

I suppose using a. engine Hoist to relieve the tension from the top might help, while using jacks and levers below to try and shift it.

Any thoughts on this and/or recommendations on how I might approach getting it into alignment?

 

[numby]

It sounds like you've just got things a little skewed. The engine to transmission to t-case bolts are all pretty strong. You can probably safely loosen the motor mount bolts and pry everything into position as a unit with a two by four. Pry against the tranny or bell housing/engine as those are all cast iron or steel. The t-case is aluminum and a little more fragile. I've done this plenty of times on other vehicles.

 

[rstoddard]

I think I figured out what happened. I was lubbing the front axel and I saw what I thought water coming out the slip joint, so I kept pumping lube trying to force it out. In doing so, I believe I F’d up and put WAY TOO MUCH LUBE in the driveshaft. I know I heard some noise, but I didn’t heed caution. Well, that noise was the driveshaft pushing the transfer case out of alignment (apparently). Seems logical since this problem arose immediately afterward.

Now I need to figure out how to release that pressure from the driveshaft and try to get things back into alignment.

If I pull the zerk fitting should that allow me to compress the slip joint and push the excess lube out so I can pull the driveshaft?

 

[hobbes]

In theory, yes. If you can generate the force required anyhow. Also, if you’ve over filled the driveshaft with grease you might consider a short drive with the zerk out unless you compress it all the way before hand.

 

[1MAC]

Pull the driveshaft out, remove the zerk and push down on it with your body weight. Make sure the zerk hole is facing in a safe direction- the grease will shoot out in a stream!

 

[pjohnson]

If that doesn't solve the problem (even if it does), I would look at your mounts on the bellhousing and see if you put the isolators back on properly. It could be lifting the rear just enough for contact.

 

[rstoddard]

How can you really gauge the correct alignment of the engine, transmission and transfer (F -R), other than how the e-brake drum should be properly aligned at the rear crossmember hump? I’m just wondering how much I should try to move it.

I pulled the Zerk (which was already oozing grease) and a gob of grease came out, so I think that released the built-up pressure. I already see some clearance from the crossmember, but not enough.

 

[B y r o n]

Another possible cause is damaged/broken motor mounts. Lowering the rear of the engine/trans/transfer case may have caused the motor mounts to break and change position causing your problem. How old are they and is it time to replace them and possibly correct your problem since it didn't exist before doing the work.

 

[rstoddard]

If that doesn't solve the problem (even if it does), I would look at your mounts on the bellhousing and see if you put the isolators back on properly. It could be lifting the rear just enough for contact.

I will check rear mounts, but I don’t think the isolators are incorrect since they were never removed; I only disconnected the three bolts from the BH on each side, lowered the tranny, and then jacked the tranny back up and bolted them back on. It seems to be pulled to the left side. It doesn’t seem to be too high. I think the clearance would be fine if I could get it pulled an inch or so to the right. It would be more centered under that hump. It just seems to be pushed against the part of the crossmember that bends Bach inward, thus creating the clearance issue.

I can only assume it was a little out of alignment to start (to the left) and my over greasing the axle forced things further out of alignment to the left.

My thoughts are to support the tranny on a Jack, take those lower motor mount bolts off the BH again (and loosen the crown nuts on the top of the mounts) and try and push the transfer to the right to gain the right clearance.

Does that seem like a reasonable approach? Appreciate your thoughts on this!!!

 

[rstoddard]

Another possible cause is damaged/broken motor mounts. Lowering the rear of the engine/trans/transfer case may have caused the motor mounts to break and change position causing your problem. How old are they and is it time to replace them and possibly correct your problem since it didn't exist before doing the work.

I’m going to look at them. What should I look for? Are you thinks lower mounts or uppers or both?

 

[fjc-man]

I think Byron means the forward engine mounts, not the bellhousing mounts. Take a look at those for damage.

 

[rstoddard]

I think Byron means the forward engine mounts, not the bellhousing mounts. Take a look at those for damage.

After rebuilding the TC (and reinstalling the Transmission after replacing the oil seal), I had to raise the engine and reconnect the motor mounts. I had been advised to losses the top mounts (so as to not to break them). I actually pulled the bolts from the top of those mounts completely (which turned out to be a mistake). Them I took the three (3) bolts off the lower rear mounts where they attach to the BH.

I’m only explaining all this to get to the point that when I went to lift the Engine/Tranny/TC and reinstall the motor mounts, I was able to connect the lower mounts, and the upper LH mount bolt, but I couldn’t get the upper RH mount bolt to line up with the hole/threads. I had to loosen everything and use a 2X4 and the Axel as a fulcrum to push the mount to line up so I could thread the bolt in.

So your point as to whether there could be a problem with the mount is a good one. To my knowledge the bolt threaded completely through and the mount was good.

Ill look to see if there is any sign of any cracking in the mount. What other sign of damage or failure should I be looking for?

 

[fjc-man]

I think that’s essentially it, bonded rubber separating from either upper or lower mount plate.

 

[rstoddard]

Is the Parking Brake Drum fully seated?

I'm stared looking closely and thinking that the Drum is sticking out too far. I don't know how I could have torqued the axel nut to 100 lbs. if the drum wasn't fully seated, unless I had the brake engaged and the brake shoes were open so far they held up to 100 lbs. of torque.

The brake works great, but something isn't right, and I don't see that much opportunity for shifting the TC to the left, so......... is this the source of the problem?

 

[Pighead]

Looks like mine...

But drier

 

[rstoddard]

Well, that is interesting. I suppose that eliminates the possibility that the drum isn’t fully seated.

THANKS!!

 

[pjohnson]

I agree with @Pighead it looks pretty normal to me. It's a head scratcher.

 

[pjohnson]

If it were me, I would loosen all the center bolts in the mounts and try to shift the rear of the drivetrain to clear the cross member.

I wonder if this is a known issue with the long AA adapter causing the tcase to potentially hit the cross member. Maybe @65swb45 Mark or @Downey Jim or @pardion John would know.

 

[rstoddard]

Well, that is interesting. I suppose that eliminates the possibility that the drum isn’t fully seated.

THANKS!!

Pighead: your e-brake drum is further behind the crossmember, but you don’t have that long 5” adapter that I have. I’m just curious, however, how it aligns behind the crossmember. I’m wondering if it’s as far to the right as mine seems to be. Is there anyway to get a photo to see how centered it is? Is there a way to measure the side of the drum (or bottom center) from the left vertical side of the frame? I’m just looking for a way to determine if I truly have an alignment issue or not.

If you can’t but anyone following can can help out, I appreciate the help trying to figure this out.

 

[rstoddard]

If it were me, I would loosen all the center bolts in the mounts and try to shift the rear of the drivetrain to clear the cross member.

I wonder if this is a known issue with the long AA adapter causing the tcase to potentially hit the cross member. Maybe @65swb45 Mark or @Downey Jim or @pardion John would know.

I was going to call AA tomorrow and ask if they have gotten any feedback on this.