Lowering subframe procedure... (advice/insight needed)

[4.2Crew]

It seems the front differential leak (gear oil) I've been chasing all Winter is NOT the passenger-side axle flange seal... After replacing THAT seal several times, I finally determined the gear oil is actually leaking from the respective differential cover plate. The O-ring behind the cover plate needs to be replaced. To do this, the sub frame needs to be lowered or removed to gain access to some of the 12 T-40 bolts securing the cover (namely the lower ones.) Any advice or insight lowering or removing the subframe?

BTW, I do have a lift and access to an engine transverse support bar...
Thanks!

[ttboost]

Been a while, but I seem to recall just supporting the engine, near the rear, loosening the front bolts about 3/4 of the way, and completely removing the K frame altogether...then run the bolts back up a little to help support the weight, leaving it hanging a just a little.

[905084]

I used a lift and my engine hoist to support the motor/trans/k member. 4 bolts for the K as I recall. Close to 1500 lbs for the engine/trans/K as it tipped my Kubota over so be careful.

[ssassc1]

Good to hear.

Quick question...

Is it possible to remove to gearbox by lowering subframe or is it engine out?

[905084]

Yes...my guy did it.

[ssassc1]

Is there a technique on how to do it?

[ttboost]

I seem to recall passenger turbo must come off...stock trans won't fit between turbos coming out...passenger side is easier to get off. You have to unbolt turbo AND undo all the oil/coolant lines...some you access from the bottom, others you access from the top as I recall...you will not have fun doing this...

[V8weight]

I kind of outlined how to support the engine and lower the subframe in this thread.. http://www.rs6.com/showthread.php/21389-What-is-going-on-here?highlight=Gutted
It wasn't necessary to remove the upper strut mounts or driveshaft though..

[ttboost]

If you have a lift, I think you can remove the whole K frame and just let the engine sit in it's mounts.

[4.2Crew]

Thanks, Pat! I did see your specific post, but still a bit confused... Where did you actually mount the transverse bar---the fender rails, or the on strut tower?

ttboost: Yes, I have a lift...Can the engine be suspended briefly using the transverse bar, then set back onto the mounts once the k-frame is removed?

....Never done anything like this before, but think it may be a valuable technique to learn!

[ttboost]

Engine never has to be lifted up. Support it from the bottom, unbolt all the bolts to the engine and trans cradle, and you should be able to slide the frame (under the trans) out, (might take a little jiggling), then snug the bolts back up. Motor should be sitting there in the motor mounts alone. You can use a pole jack to help support some weight.

[4.2Crew]

Engine never has to be lifted up. Support it from the bottom, unbolt all the bolts to the engine and trans cradle, and you should be able to slide the frame (under the trans) out, (might take a little jiggling), then snug the bolts back up. Motor should be sitting there in the motor mounts alone. You can use a pole jack to help support some weight.

Ah, know I get it!... Thanks ttboost! From your description and the attached pic, it's now obvious the motor mounts do not just attach to the subframe---like I thought they did. The motor mounts attach to a bracket which attaches to another crossmember AND the subframe.

One more question: In the attached pic, what is the other circled component---just rearward of the PS output flange? Is it part of the transmission mount? It has a spring attached...

15118

[ttboost]

Ah, know I get it!... Thanks ttboost! From your description and the attached pic, it's now obvious the motor mounts do not just attach to the subframe---like I thought they did. The motor mounts attach to a bracket which attaches to another crossmember AND the subframe.

One more question: In the attached pic, what is the other circled component---just rearward of the PS output flange? Is it part of the transmission mount? It has a spring attached...

15118

Yes, I think you have it now.

I think that other circled part is part of the downpipe. I seem to recall a small bracket with the spring on it on the downpipe itself, that mounts to the trans.....

[4.2Crew]

Yes, I think you have it now.

I think that other circled part is part of the downpipe. I seem to recall a small bracket with the spring on it on the downpipe itself, that mounts to the trans.....

Thanks.... Never done this before, but gotta believe with the subframe removed, it opens up a lot of space and provides tons of otherwise limited access? Perhaps swapping to a bufkin pipe too?