Are shims still needed after cab mount replacement?

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waterpirate

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After trying to re install my front clip, we took a porta power to both sides to help with alignment. This stuff is not as easy as any video you watch. They cheat, big time with time lapse and editing. Being patient is key, and if pissed off do something else for a while and come back to it.
Eric
 

Randy and Easton

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As Rusty would say(we miss him so much?

"pix?

[older but popular pop culture reference] and [direct insult] but [redeems the insult with witty remark] because [pls show pics we show u ours]"


RIP rusty wherever you are relative to your computer
Pics of the shims or the fenders not aligned?
 

Big Chip

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Poly cab mounts are known to be haywagony although last time they are needed.
Well, lady shiftpro, I must have gotten some super special ones then. My truck rode a bunch better after the poly mounts and my old ones weren't all blown out.
 

Keith Seymore

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After trying to re install my front clip, we took a porta power to both sides to help with alignment. This stuff is not as easy as any video you watch. They cheat, big time with time lapse and editing. Being patient is key, and if pissed off do something else for a while and come back to it.
Eric
What did you do with the porta power? It was required even with the bolts loose?

Normally, we would leave the radiator support loose, just sitting on the mounts. The LH fender would go on, sitting on the cab (on the designated* shim pack) and then drive the vertical rear bolt.

We would then open the door, drive the horizontal top rear bolt (tight) against it's designated* shim pack and then loosen the vertical bolt a bit, so it was no longer torqued down.

While all this is going on another guy would be driving the 7 (I think there were 7) nose bolts in the front of the fender to the radiator support.

After the LH rear guy was done he would then take a big stick and pry rearward on the dog leg portion of the fender, pulling it back towards a fixture to set the gap to the door, while the guy in the pit drove the bottom anchor bolt tight against his designated* shim pack.

We would leave everything loose assembled like this until after the hood was installed and fit (you should be able to slide the radiator support crosscar by hand, squaring the opening so the hood gaps are even). Then all remaining bolts got torqued down.

All this happened in about 45 seconds. All day. Every day.

While I was foreman on the line in this area I watched them do about 900,000 trucks (or 1.8 million fenders) over a six year period.

K
 
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Keith Seymore

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designated* shim pack
I used the term "designated" shim pack because we would not fit each individual truck. There simply wasn't time.

We built to "trends", that is, we got it pretty close and then ran every truck exactly that way, whether it needed it or not, until the repair foreman out back would call and demand we make another adjustment.

What we used to do for fender shims is tape a packet together, like 3 shims, and we would run those all day whether the truck we were currently building needed it or not.

Eventually the final repair supervisor would call back and say something encouraging, like "SEYMORE!! YOU IDIOT!! WTH ARE YOU THINKING?!?! ALL THESE FENDERS ARE RUNNING HIGH!! ARE YOU EVEN LOOKING AT THESE TRUCKS?!? TAKE A SHIM OUT BEFORE I COME BACK THERE AND SHOW YOU HOW TO DO THIS!!" I can just imagine the spittle flying into the phone mouthpiece.

So we would start running a new shim pack, like 2 shims, until he called again with his latest observation.

Basically it was to address "macro trends". You had about 45 seconds to complete the truck in front of you and move to the next one; that's not enough time to fit and re-fit each individual truck.

There was a repair station at the end of my area. There was also a short moving repair line (two, actually) at the end of final line. If they could fix them there while on the move then they would; otherwise it would be out to a stationary repair stall in "heavy repair" for the really bad ones.

I should add that most of the repairs did not consist of removing the bolt or adding/deleting shims. Often the repair consisted of bending, twisting or hammering while the line was moving.

K
 
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AuroraGirl

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Well, lady shiftpro, I must have gotten some super special ones then. My truck rode a bunch better after the poly mounts and my old ones weren't all blown out.
I mean its possible. It also depends on the mounts and the setup. If your cab wasnt secured in the right procedure on the old ones it was probably a nightmare, yeah, but Ive heard the rubber ones are also not all that great for these gen trucks either.

something as simple as a ground out to the metal sleeve mmiddle piece could be issue too.

Im glad it worked!

Was your pickup or suburban?
 

Big Chip

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I mean its possible. It also depends on the mounts and the setup. If your cab wasnt secured in the right procedure on the old ones it was probably a nightmare, yeah, but Ive heard the rubber ones are also not all that great for these gen trucks either.

something as simple as a ground out to the metal sleeve mmiddle piece could be issue too.

Im glad it worked!

Was your pickup or suburban?
The fact of the matter is that poly bushings work for most people. I suspect the problem some people have lies with a lack of lubrication and improper torque but who knows? I have a pickup and when I installed them I feel the ride improved. It seemed to have more torsional rigidity and therefore better handling and ride.
 

Frankenchevy

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After trying to re install my front clip, we took a porta power to both sides to help with alignment. This stuff is not as easy as any video you watch. They cheat, big time with time lapse and editing. Being patient is key, and if pissed off do something else for a while and come back to it.
Eric
After installing my poly mounts, everything mostly lined up from the cab forward, but I had to shim the rear driver’s side cab mount for the body line to line up properly between the cab and bed. It was off about 1/8”. Just used a hardened washer.
 

shiftpro

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Well, lady shiftpro, I must have gotten some super special ones then. My truck rode a bunch better after the poly mounts and my old ones weren't all blown out.
If your original mounts were completely blown out maybe the cab was sitting on metal. In that case then yes your poly mounts would feel better.
 

shiftpro

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After installing my poly mounts, everything mostly lined up from the cab forward, but I had to shim the rear driver’s side cab mount for the body line to line up properly between the cab and bed. It was off about 1/8”. Just used a hardened washer.
It helps to have a really level shop floor. Failing that, put a level on the diffs and shim under the tires to level the 'feet'. This is assuming the suspension isn't sacked.
 

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