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Old 12-17-2015, 02:15 PM   #26
Orange Crate
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Re: Transfer case torque mount

haskins10;
You had other issues going on before that failure, it wasn't because you don't have the torque mount. I would guess that your trans mount was toast and let loose, allowig the rest to bounce around.

jaros44sr;
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Old 03-11-2017, 01:47 PM   #27
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Re: Transfer case torque mount

I know this thread is a few years old, but wanted to post what I found in order to help future visitors. The picture in #7 is correct. If you look at the lips when you have them apart you can tell that they have worn a pattern to each other. I just tore 2 of them apart and the lips were facing each other on both. Hope this helps!
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Old 03-18-2017, 09:25 AM   #28
mattfrediani
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Re: Transfer case torque mount

can someone tell me how much torque i should put on these new torque mount poly bushings? gorilla tight or snug?
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Old 03-18-2017, 12:08 PM   #29
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Re: Transfer case torque mount

Just snug them, the poly mounts are harder than the rubber & you want some give in it. If it is super tight you are more likely to break your tcase adapter. also, as stated earlier (many years ago!), check your motor mounts, if the driver's side breaks (and they are notorious for breaking) it will break your tcase adapter.
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Old 03-18-2017, 12:35 PM   #30
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Re: Transfer case torque mount

I have upgraded the tranny, and case with poly mounts, I want to do the motor now.
Is it hard to just lift the motor with a block of wood at the pan and remove the old rubber and get new poly mounts in?
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Old 03-18-2017, 02:52 PM   #31
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Re: Transfer case torque mount

I'd use a floor jack on the oil pan with a couple of blocks of wood to protect the pan. Loosen all other mounts before lifting engine. If you have an engine hoist you can raise the front of the engine, you still want to loosen all your mounts first.
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Old 05-04-2017, 10:58 PM   #32
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Re: Transfer case torque mount

so where can one get the case rubber bushings?
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Old 05-05-2017, 02:40 PM   #33
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Re: Transfer case torque mount

Quote:
Originally Posted by mike16 View Post
so where can one get the case rubber bushings?
Rubber, I don't know, prothane has poly
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Old 05-14-2017, 12:54 AM   #34
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Re: Transfer case torque mount

I just finished pulling my adapter mounts and torque plate rubber bushings apart to clean inspect and re-install them. Attached are a few images I hope they help.
The torque mount is critical, It provides a whole different purpose than motor mounts or the adapter/tanny mounts.

Motor mounts and the adapter mounts fix the engine, transmission and transfer case in place, For the most part they support the weight of the drivetrain and its weight generaly fix them or hold them in place. The only fasteners that hold the engine in place do not pull it together from top to bottom but are installed to simply hold the two parts of the mount system, the frame mounts and the engine mounts together. weight keeps them pretty much in place. the through bolts hold everything together and prevent the engine from rocking too much either left or right. They dont hold anything in tension.

Ditto for the transfer case adapter mounts. its the weight of the drivetrain that holds them in place. the through bolts simply keep everything snugged up and in place. That being said, those bolts dont need to be very tight. I looked at mine and noted how much of the bolt protrudeds above the adapter before dis assembly( digial camera an absolute must). and turned the bolt untill about the same amount extended beyound the cast iron adapter upon re-assembly. No torque for two reasons...1. too much torue is not needed and is detrimental, too much torque preloads the mount and does not allow it to do its multifunctionl job, 2. those special lock washers, available cheap from several vendors when used...properly keep the bolts tight and prevent them from backing out.

Any "preload" should come from the weight of the drivetrain and NOT,NOT from over tightening those bolts. when the full weight of the drive train rests fully on the mounts witch will settle a bit and bulge out a bit. thats typicle and acceptable. But once you do that, do not continue to tighten up those bolts untill the rubber mounts distort further, maybe a very slight amount of distortion but no breaker bars with 4 foot pipe sections on the end. It does not work like that and too much Preload from tightening will surely brake the adapter. the weight of the drivetrain holds everything in place, the fastener keeps everything fixed in place and that strange little lock washer prevents it all from comming loose. Not massive amounts of torque from a breaker bar.

Another thing that worked for every in the past and workes even better now is a caulking tube of RTV window and bathroom sealant. Its 4.99$ at Ace and I use it to Litteraly Glue the upper and lower tranny adapter mounts together. The current mounts are one size fits all and there are alot of sloppy fit, airgaps around the mount where it interfaces with the cross member. so I fill in the gaps, including serious ones around the steal tube through bushings/sleave that goes around the through bolt. I slop it all up with the seallant. I tighten up the through bolt and let it sit for a full 24 hours.

Note: I have not attached or fixed the crossmember to the frame. the trany is supported by a floor jack and wood blocks.only the glued mounts are slightly fastened to the crossmember for the 24 hours.
24 hours later I loosen the tranny adapter through bolts so that the cross member is flopping around loose to the frame and the tranny adapter.
then I tighten up the cross member to frame fasteners
then I tighten up the tranny adapter mounts to the adapter. then I lower the jack so the full weight of the drive train is resting on the mounts/crossmember

then I tighten up the through bolts untill just a slight additional amount of distortion is percieved at the rubber mounts.

then I bend the lock washers such that they prevent the through bolts from lossening

Points to remember:
If your motor mounts or tranny mounts are bad ,failed, soft or oozing. they need to be replaced. If not, other things will break on a regular bassis untill you get it.

tightening the tranny adapter mounts too much, defeats thier purpose and will increase the chance the tranny adapter will fail. Tighten Just enough to see a little more distortion beyond what the full weight will do. Just a little. Use the lock washers to prevent loosening of the fastener/hardware. torque does NOT do it, lock washers do.

It must be remembered that these trucks were not envisioned to be rock crawlers or mud boggers. They were intended to provide conservative operational mobility over rough terrain.The frames flexed, that is normal. four wheel drive flexed even more, and with a load in the bed they flexed even more. the engine, bellhousing transmission, adapter and transfer case were not flexible and if they were fixed firmly to the frame they would crack everywhere and bust out chunks of cast iron. And with this knowlege and several years warrenty experience. It continued to be a problem and some might agree it got worse as trucks became more powerfull, heavyier and used with more wreckreational enthusiasm.

So its important that the mounts be good and not oozing, dryrotted or broken.

The torque Mount
That Torque mount serves a totally different purpose and if its not installed there is a different but equally likehood that the tranny adapter will fail.

Think about it, torque is twisting motion, the torue mount allows a little bit but limits the twisting force of torque beyond the engineered limits.

You have a six, an eight or a bigblock providing twisting force, then there is a flywheel, then low gear, a low range in a two speed transfer case, 456 gears, and what ever tire size is factory recommended. when all tht twisting force meets the ground something must give a little bit because the tire grip is fighting the drivetrain forces and your engine wants to twist, your tranny and t case want to twist. when the t case wants to twist engineers said ok, a little is nessessarry and even good but it cannot be allowed to twist the rest of the drivetrain or other components will fail. And it cannot, nay.. must not be to ridgid because it will weigh too much and will never be totally rigid. little flexing is OK, even good for noise comfort levels.

that tcase torque mount allows the t case to float under normal load, but as torque winds up the drivetrain the t case will try to rotate, loading up the mounts and it could cause damage if allowed to twist too far. so under normal load it floats and the bushing rubber mounts and ,again, just kinda held in place but as it winds up the mounts come into play and resist further twisting force so that the torque does not wtist or damage other parts.

It looks kinda flimsy and loose but thats at normal loading. You will note that it extends out from the side of the t case and only a little bit of moment arm is all that is needed to stop the t case from twisting further. Thats all it does is prevent exessive twisting of the back of the engine/tcase.it keeps the compression load of the t case adapter from becomming a twisting load that will snap off either an aluminum or a castiron adapter,

The engineers put it in there for a reason, It took labor to design, test and assemble and install it and it cost to cover it under warrenty. plus the actual cost of the parts them selves and not to mention the logistics of keeping spares in the invantory.

Think about it. thats a very expensive part were it actually to be so unnessassarry. and to be the cause of so much additional part failure.

I worked in the army as a wheel mechanic and later as a contractor.

Those adapters faile often in the cucv's. in every case the cause wqas one of two things, either the adapter mounts were too tight and or the t case mounts were tightened up to spec BEFORE the transfere case was installed.

I saw one soldier brake one adapter between 8 and noon, the second one by 2 pm and befor 4 he had broken a third one.

On civilian trucks when you put heavyier springs shocks and big azz tires on these old girls a third possibility for failure occurs. all the torque is consentrated between the flywheel and the drive shafts, that twisting motion and ressistance consentrates the tourque between fewer and increasingly "underengineered" Parts. Somethings gotta give.

it may be u joints. drive shafts but eventually the mounts will fail. and not the cheap replaceable rubber mounts but the expensive hard to find, expensive to ship, gets lost in the mail, tranny adapter

Last edited by mike16; 05-14-2017 at 01:47 AM.
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Old 05-14-2017, 01:07 AM   #35
mike16
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Smile Re: Transfer case torque mount

attached are some images of the torque mount and adapter mount.

I glued the adapter rubber mounts to the crossmember and filled in any air gaps or spaced. the current after market tranny mounts are a sloppy loose fit all around but work when the weight is fully on them. but there are two steel sleaves or tubular bushings that slid up into those mounts. There is alot of airspace and gaps around what should be normally very well supported. I filled it all in with the RTV sealant caulking.

I got the sealant at Ace. for 4.99 vs about 1 fifth that amount from NAPA for 8 bucks.

glued it all together, snugged up the fasteners and let it vucanise for 24 hours.

when its all dry I trim off the exess with a razor.

the t case adapter rubber mounts were brand new . the t case torque rubber bushings were origonal and in good shape. I cleaned them off with GOJO type hand cleaner. Its very forgiving and does not rot them like petroleum based cleaners do. protects and softens and they shine like new.

I hope the pictures help. especially with missing parts and correct reassembly.
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Old 05-14-2017, 01:14 AM   #36
mike16
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Re: Transfer case torque mount

I use GOJO handcleaner to clean off dirt and grease. It protects the origonal painted finish, and harmlessly cleans up rare, impossible to find rubber bushings. I also use simple green and it too is very forgiving.

the caulking gun is filled with an RTV type caulking substance in a dark grey pigment, white and clear are also available. I accidentally bought some black roofing asphalt/cement . wrong stuff. read the label and avoid multi trips to "the place". after it dries for 24-48 hours trim exess ooze with a razor.

One more thing I keep harping on. tightening hardware will not ensure that it stays tightened. lock washers do that. It works witht the t case adapter rubber mounts, and the torque mount wher the brackets fasten to the fram c section and the torque mount through bolts.

dont over tighten. If your motor mounts are bad in any way or over 2 years old... replace them and the t case adapter mounts and if you can, salvage the rubber torque mount rubber bushings, or replace them with the prothane bushings, If ya gotta replace one component, replace them all. do them all at once. its the best 100 bucks you can spend

I hope I have helped
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Last edited by mike16; 05-14-2017 at 01:32 AM.
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