Rearend alignment HELP!
#1
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Rearend alignment HELP!
Recently on a trip home (from Fort Stewart to Panama City) my front tires got completely eaten up. So I figure it is my alignment and I take it in. The mechanics fix the front alignment, but show me on a computer print out that my rear is crooked. They said they had to drop the rear leaf springs drill some new holes and mount it back really tight to keep it straight. There hasn't been any irregular wear on the rear but I am still worried. Does this sound right? Is there any other solution? I have a 99 z28 m6 with 83,000 on it. Thanks for the help.
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My advise is take it to another shop. Leaf springs haven't been on f-bodies since the 70s.
We have coil springs and they have absolutely nothing to do with thrust angle.
If the thrust angle needs to be adjusted, you will need adjustable lower control arms. If the pinion angle is off, you will need and adjustable torque arm. An adjustable panhard rod wouldn't hurt either. I would get everything from www.lgmotorsports.com ... they are more expensive than most, but they are definitely worth it. Give them a call...they can answer all of your alignment questions.
We have coil springs and they have absolutely nothing to do with thrust angle.
If the thrust angle needs to be adjusted, you will need adjustable lower control arms. If the pinion angle is off, you will need and adjustable torque arm. An adjustable panhard rod wouldn't hurt either. I would get everything from www.lgmotorsports.com ... they are more expensive than most, but they are definitely worth it. Give them a call...they can answer all of your alignment questions.
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Great thanks for the help. I knew something didn't sound right but the people who owned the shop go to my church. I will give them the benefit of the doubt maybe they haven't worked on this sort of problem. Thanks for the advise though, I was thinking the same thing about the panhard rod and torque arm. Thanks again.
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Pinion angle is in the vertical plane (set by
the torque arm and axle height relative to
body).
Thrust angle is in the horizontal plane and
is set by the lower control arms & their
mounts.
To have a rear end misalignment you would
almost certainly have to have bent some
mount (or have adjustable LCAs, which
were misadjusted). On a stock rear it's
well nigh impossible to have a really bad
thrust alignment. Much lower odds than,
say, running across a weasel at a tire shop.
Rear end being out of line would result in
some "crabbing" but it's not going to chew
the fronts, unless your front align changes
a whole lot from a little off-axis steering.
In which case, you would chew the fronts
anyway every time you turn.
the torque arm and axle height relative to
body).
Thrust angle is in the horizontal plane and
is set by the lower control arms & their
mounts.
To have a rear end misalignment you would
almost certainly have to have bent some
mount (or have adjustable LCAs, which
were misadjusted). On a stock rear it's
well nigh impossible to have a really bad
thrust alignment. Much lower odds than,
say, running across a weasel at a tire shop.
Rear end being out of line would result in
some "crabbing" but it's not going to chew
the fronts, unless your front align changes
a whole lot from a little off-axis steering.
In which case, you would chew the fronts
anyway every time you turn.
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Originally Posted by seabassz28
The mechanics fix the front alignment, but show me on a computer print out that my rear is crooked. They said they had to drop the rear leaf springs drill some new holes and mount it back really tight to keep it straight.
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can you explain "crabbing" please?
leaf springs? they should at least know what those look like if they are mechanics, no matter how bad of a mechanic they are!
I'd like to know what they did to your car...
leaf springs? they should at least know what those look like if they are mechanics, no matter how bad of a mechanic they are!
I'd like to know what they did to your car...
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#8
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They fixed the front alignment, but I didn't let them touch the rear. Like I said something didn't seem right if the wheels cant to the left as looking from it from the rear would the lca's correct that? It kinda looks like this on the computer print out:
\------()------\
the \'s being the wheels and the () being the differential
\------()------\
the \'s being the wheels and the () being the differential
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[QUOTE=skippytheloon]can you explain "crabbing" please?
QUOTE]
If you ever saw one of those crabs on the beach, they
don't walk straight ahead, but sort of scuttle diagonally.
A car that's "crabbing" has its body pointing somewhere
other than the direction it's going. You see this a lot on
leaf-spring 4x4s that have bumped over too many rocks
and gotten the axle cocked. Funny when you do see it.
QUOTE]
If you ever saw one of those crabs on the beach, they
don't walk straight ahead, but sort of scuttle diagonally.
A car that's "crabbing" has its body pointing somewhere
other than the direction it's going. You see this a lot on
leaf-spring 4x4s that have bumped over too many rocks
and gotten the axle cocked. Funny when you do see it.