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Hello,im installing a tubular crossmember purchased from Clear Image and i also have a energy suspension transmission mount that came with it,being that this mount now goes on a different location on transmission (for those that are not familiar with the 4l60e,it has two mounting locations for the mount),well with the tubular crossmember the mount is relocated closest to the transmission pan...with that being said can anyone help me as far as the spacers that came off the old mount,how many have you used when doing this installment? The energy suspension mount comes with one spacer and its mandatory as far as the instruction say,then im left with the two orginals that came of old mount.also the new location sits lower than old location, dont want to mess up pinion angle,can anyone help as far as how many shims to use or what you did when you installed yours,thanks

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1996 BBB
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Easiest way is just to take an angle gauge/digital level and put it flat on trans pan, check it with the old setup and just match it. That's not really the most accurate way for checking pinion angle but assuming your car is stock and worked fine before, matching what you had before is probably the best bet.

With that said, one or two .120 spacers won't really make much difference in the angle, I would doubt you'd see any drivetrain issues with or without them but can't hurt to match where it was before.
 
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I just installed one of these mounts (have to do some modding to install my TCM) and I only used the one spacer that it came with. Pinions look good (my car is lowered) and there are no new vibrations. I say new because I need to get my tires balanced.
 

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It would have been ideal to have measured the height of tail shaft before removing old X member and then matching that with the new one using either 0-3 of the shims.

The measurement should be done with the car raised at whatever height you are working on it so there is no change in car position installing new X member

IDK if Clear Image makes the X member or just resells the BTO one, which is what I have. I wound up using the 2 stock shims but I also maintained my rubber trans mount (T/56). I assume the 4L60 E X member is diffrent but FWIW I also had a BTO tubular for it and also used the 2 stock shims only.

Just check DL angles and add/subtract as needed. And yes each 1/8" thick shim makes a angle difference...its why 1 or 2 came with the car
 

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It would have been ideal to have measured the height of tail shaft before removing old X member and then matching that with the new one using either 0-3 of the shims.

The measurement should be done with the car raised at whatever height you are working on it so there is no change in car position installing new X member

IDK if Clear Image makes the X member or just resells the BTO one, which is what I have. I wound up using the 2 stock shims but I also maintained my rubber trans mount (T/56). I assume the 4L60 E X member is diffrent but FWIW I also had a BTO tubular for it and also used the 2 stock shims only.

Just check DL angles and add/subtract as needed. And yes each 1/8" thick shim makes a angle difference...its why 1 or 2 came with the car

It does make a difference in the angle, but don't think i've ever encountered a car that had a driveline vibration that was fixed by 1 .120 shim. I suppose there could be a tolerance stack up to where your driveline angle is so badly out that 1 shim brings it back over the threshold of vibration but usually when I have seen cars with a vibration due to pinion angle, it was way off (on our cars usually due to adj control arms not being adjusted correctly throwing angles out a decent amount).

You're definitely right though, to get it correct it should be matched, and for peace of mind and longer U joint life it's probably worth doing, just saying it's probably not something he'll likely notice if he doesn't.
 

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well I can say from direct experience that going from 1 shim to 2 as my stock 4L60 had when I did my T56 swap did resolve a "slight" high speed DL vibe....hence why they are made in 1/8" thickness. Sometimes none are needed and others 1,2 or 3 or 4. I have 4:10 gears and a Dennys 3.5" DS and DL angles are perfect now...it just took 2 tranny shims to nail it.

My 67 Camaro I lowered using blocks on rear (2") and had to raise trans. Wound up needing 4 shims (1/2" total) even after adding a 2 degree shim over the lowering block...so yeah 1/8" makes a difference of keeping it in or out of the vibe zone. YMMV
 

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well I can say from direct experience that going from 1 shim to 2 as my stock 4L60 had when I did my T56 swap did resolve a "slight" high speed DL vibe....hence why they are made in 1/8" thickness. Sometimes none are needed and others 1,2 or 3 or 4. I have 4:10 gears and a Dennys 3.5" DS and DL angles are perfect now...it just took 2 tranny shims to nail it.

My 67 Camaro I lowered using blocks on rear (2") and had to raise trans. Wound up needing 4 shims (1/2" total) even after adding a 2 degree shim over the lowering block...so yeah 1/8" makes a difference of keeping it in or out of the vibe zone. YMMV
That's exactly what i'm talking about, the larger changes could have put things far enough out that one shim brings it back into the clear as far as vibration. One shim under the trans mount though changes driveline angle only VERY slightly, less than a half degree IIRC, and from the factory most of these cars I have checked were pretty squarely within a range where vibration shouldn't be present even with a half degree added to either direction. Of course, can't rule out the fact that the aftermarket crossmember may be way off from the factory one, or a tolerance stack up or what not.

Just saying on the typical factory car, I have rarely seen a situation where one shim makes or breaks it as far as vibration goes. You're definitely right that he should check though, as there's no way of knowing how close the aftermarket crossmember is to the factory one. It could already be on the high side for example and adding the two shims back might create a problem that wasn't there before.
 

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Discussion Starter · #9 ·
That's exactly what i'm talking about, the larger changes could have put things far enough out that one shim brings it back into the clear as far as vibration. One shim under the trans mount though changes driveline angle only VERY slightly, less than a half degree IIRC, and from the factory most of these cars I have checked were pretty squarely within a range where vibration shouldn't be present even with a half degree added to either direction. Of course, can't rule out the fact that the aftermarket crossmember may be way off from the factory one, or a tolerance stack up or what not.

Just saying on the typical factory car, I have rarely seen a situation where one shim makes or breaks it as far as vibration goes. You're definitely right that he should check though, as there's no way of knowing how close the aftermarket crossmember is to the factory one. It could already be on the high side for example and adding the two shims back might create a problem that wasn't there before.
Exactly.... if I put the 2 shims back on I feel it would be off,remember that the mount is now in a different location to fit the Cia crossmember and it sits lower than the old location, I put it on with the supplied spacer which is mandatory per instructions,and left of the 2 orginal shims,and it looks level and angle looks good,won't know for sure until I drive it and currently I'm still putting it together, I did a frame off restoration and been slowly putting it back together.
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Car Looks great! Are you running aftermarket adjustable trailing arms? If you are I would pick up a $5 angle finder gauge from harbor freight and check the pinion angle and engine/trans angle and that will give you definitive answer on whether or not everything is good. even if you're not running the adj trailing arms, it's easy/cheap enough to check for peace of mind.
 

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Discussion Starter · #11 ·
Car Looks great! Are you running aftermarket adjustable trailing arms? If you are I would pick up a $5 angle finder gauge from harbor freight and check the pinion angle and engine/trans angle and that will give you definitive answer on whether or not everything is good. even if you're not running the adj trailing arms, it's easy/cheap enough to check for peace of mind.
Oh wow ok definitely gonna swing by Harbor freight and pick that up,i love that place lol,yes adjustable uppers...thanks
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I just did same to my car. I checked with angle finder on trans pan both before and after. Dead nuts on. No need for me to use factory spacer, just what came with new mount. FLABOY777 yours is looking awesome!
 

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FLABOY777 and SSandman which adjustable upper trailing arms are you running? My tailshaft and rear pinion u-bolt angles are 5 degrees after lowering the car and I'd like to get them below 3. I'm thinking of going with Spohn uppers.
 

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Nice paint work and ALL! Thanks for pic of CIA crossmember and ES transmount pad on the car. I'm just getting ready to do the same job as soon as the bar arrives. You might want to look at this video to help you determine exactly what your driveline angles are with the new gear in there. There's also Spicer.com to help you crunch the numbers on the digital angle finder.
 

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Discussion Starter · #17 ·
FLABOY777 and SSandman which adjustable upper trailing arms are you running? My tailshaft and rear pinion u-bolt angles are 5 degrees after lowering the car and I'd like to get them below 3. I'm thinking of going with Spohn uppers.
Hey just seeing this until now,but i got QA1 adjustable rears and non-adjustable lowers.
 

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Discussion Starter · #18 ·
Hey just seeing this until now,but i got QA1 adjustable rears and non-adjustable lowers.
I went woth QA1 because they were available at my local Summitt, plus they are really nice and they offer all other components for your suspension, i got the front and back sway bars aswell,still saving for the coilovers but I'll have them one day.
 

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Because there are ways to adjust the pinion angle with fixed arms but it includes welding.
You can remove the upper bolts and slide long 1/4 or 5/16 bolts through.
Push the diff to load the bolts, measure the change.
From there you can figure the exact amount the arm length needs to change.
Weld up arm holes, move holes, stitch washers on arms to reinforce.
 
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