Z Height Setting In Factory

[revrnd]

When I was in the Oshawa Truck Plant for the 1st year of GMT400 production, the z height was set by an employee working underneath in a pit w/ a setting fixture attached to the LCA bolts & an air wrench to adjust the bolts.

 

I returned to the plant in '97 just before the start of the GMT800s, thru to the GMT900s until last Dec'. I wasn't working on the final line where the Z height was set on the GMT800s, but did notice that there wasn't an operator setting the Z height there. Any idea as to how they are setting the Z height currently on the trucks? Have they just moved the operation to the chassis area of the assembly plants or does the operator just wind the bolts in "X number of revolutions"?

 

Just wondering if it's a hit or miss adjustment or done a different way. I'll have to stop & ask a friend who runs an alighnment shop how they find the Z height settings on the GM trucks they service. I have heard some people say that they've gotten trucks that the fender height measurements have differed from 1 side to the other.

[oldschool327]

My 05 Colorado was off by 3/4 of an inch left to right from the factory.

[dlstewart01]

I guess you never herd of the famous chevy lean. All GMt 800s lean to the left some what. If its not out more then 1/2 inch GM would say its normal. Truck must be on LEVEL ground to be measured. 4 whell drives can be adjusted by the torsion bars. Two wheel drives were adjusted in the front with coil spring spacers. The rear leaf springs were adjusted with a flat spacer. Got one of those on my work bench.

 

There is a TSB on this. I am too lazy to try to find it right now, Maybe MS3DALE can find it better than I can anyway.

 

I learned never to take a tape measure to my truck. None of them are level.

[brims]

I learned never to take a tape measure to my truck. None of them are level.

 

I think GM adopted that thinking on the alignment of these 900s. "Just send it out for delivery"