StreetLethal

I had an issue when I got my alignment done where the rear thrust angle was off after the front was adjusted. The shop adjusted my steering to compensate and said that there wasn't anything else they could do about it.
I really don't know much about alignment at all, but is this a major concern? It doesn't seem normal but any input would be appreciated. Could some parts be worn in the rear or possibly a frame issue be present?

Here is the sheet:

Chronicle

iTrader: (7)

A. I'd like to know too, since I thin I had this problem when I aligned my wheels.

B. WTF? You live in Annapolis? I'm like 45 minutes away from there.

BlackScreaminMachine

iTrader: (17)

Post this in the Suspension Forum, you may get a guy like Strano to comment. To be honest if there is absolutely nothing adjustible on the car, chances are something could have taken a wack in the past.

My brother was an alignment tech and I will ask his opinion but I do know in the past I had a 86 Honda Prelude had to have been hit as the Caster (which is a fixed val) moved back a good bit and they figure it was bent. The car kinda sucked anyways so I was not sad to see it go but regardless.

71novaguy

iTrader: (2)

correct me if I'm wrong, but thrust angle is refering to the the angle of the rear end. Meaning the rear axle is not straight with the front end which causes dog legging, or the rear axle is facing slightly left or right which makes you steer the opposite direction to correct it.

I would agree with this thing taking a whack in the past, which is why I am curious why the caster on each side is different. I know it all has a range, but caster effects how easy the car is to steer down the road. I would check the straightness of the rearend and look for loose or broken parts. It appears it is crooked by looking at the range of the toe, which makes it appear the rear end is off towards the left.

StreetLethal

That makes sense to me especially because the car tended to pull toward the left before the alignment. Everything looks normal on the reaend at a glance, but I know that the left quarter panel has had work done on it at some point because it doesn't line up with the taillight quite right.

It seems that the thrust angle was fine before the alignment, but only beause the front was also off. Now that the front is correct, the rear not being straight shows.

The question now is: Is this something with the rear/axle that I can get fixed, or do I have an issue with the frame throwing it off?

StreetLethal

Yes, sir. Right near downtown.

StreetLethal

Any way a mod could move this to the suspension forum please if necessary?

Pilsner

iTrader: (4)

-Thrust angle should not change from before to after since it's not adjustable. But is adjustable with adjustable rear control arms.
-Rear toe and camber is not adjustable, solid axle.
-Frt Caster/Camber is adjustable with a LCA eccentric.

Your car was probably hit in the rear at some point.
The alignment specs look ok, you have .5 pull to the left and zero toe. It should drive pretty good.

If you want to make it perfect get adjustable rear LCA and realign, but this may cause the rear wheels to be uncentered in the wells.

StreetLethal

Thanks for the input. How is the shop saying that the rear thrust angle changed in this case? It is relative to the front end alignment? Since a solid rear axle can't be adjusted I don't see how they could say it was different afterwards.

71novaguy

iTrader: (2)

if they are a reputable shop, I would ask them to throw it on the rack again and see how it looks now. I almost wonder if they didn't settle the car correctly before alignment, or after alignment. meaning they should shake the car a few times to make sure the car is settled on the rack before and after alignment. I could almost see the adjustment on the front end making your rear see out of alignment if it wasnt allowed to settle. how does the car drive?

StreetLethal

It drives pretty nicely. When they ititially did the alignment it actually pulled to the right with the wheel centered pretty strongly. After that they adjusted the wheel and it drives fine now. My concern is that the only reason it drives fine is because they compensated.

Pilsner

iTrader: (4)

Settling the suspension will not change the tracking.
Did they check for worn/loose rear lower control arm bushings?

Centering the wheel will have no effect on the alignment angles other than the front toe. When centering the steering wheel you are matching the "track" of the frt wheels to the rear wheels.

jimmyblue

iTrader: (11)

If the frame isn't bent, then it is what it is. Which is, a
big "don't care". You can't see or feel 0.18 degrees worth
of crabbing. And you don't know what their accuracy and
repeatability is for that measurement either.

However the printout plainly shows that they "caused"
it, so go have some fun with them if you want to.

StreetLethal

No, I don't think they checked for anything. To be honest I think they did a crappy job. They told me that one of my tires was getting due for replacement but that was it. It was just the local Mr. Tire. I'm thinking I need to find a better shop in the area.

CO99Z28Vert

iTrader: (30)

Wow first off all there is no Ecentric bolts anywhere on the front of your car as said previously and second why are you so concerned about a simple alignment?
Do you know how a Hunter machine works? If those tards accidentally bumped a head in the rear at anytime during the alignment then the readings will be off.

Your car was obviously pulling before due to the camber and you said it was fixed so whats the big deal? The rear end is NOT adjustable without aftermarket parts so obviously the shop didn't do anything to it.

I am an extremely helpful guy and if a customer wants to know anything about the car they bring in while I am working on it I will explain it to them until they get sick of hearing about it. When it comes to alignments and bitchy customers I always make sure the readings are perfect before giving them a printout...even if the part is non adjustable because **** happens with the machine and I will change specs to reflect it.

Pilsner

iTrader: (4)

-You can get front LCA eccentric, they are not stock. Strano sells them.
-As for the specs changing, the alignment tech should check for any loose suspension components BEFORE an alignment to ensure the readings are correct and will NOT change during the alignment.
-The before measurements may have changed due to a loose head or whatever, but there should have been a resweep to show the correct angles before giving a printout to a customer. Do you agree?

CO99Z28Vert

iTrader: (30)

I absolutely agree with you, anytime an alignment is performed a suspension check is in order especially checking for worn ball joints or tie rod ends.

I do agree that the tech should have never let a car leave with that reading for the rear. He should have rechecked and if it was something that was the machines fault then he should had modified the specs or checked the head to get that perfect reading so the customer would not be concerned.
My only thing is obviously the rear is non adjustable and there was nothing the tech could have done on the front of the car to throw out the rear specs other than bumping the head or dropping the car off the rack lol.

I just have had my fair share of witnessing other techs get bitched at from customer complaints because they let a perfectly good alignment roll out with some printouts in the red and customers get all worked up about it, even though the rear end was weighed down with **** in the trunk and didn't have adjustable parts...for this reason alone I always make sure the printouts are perfect even if I have to mess with a head.

Pilsner

iTrader: (4)

I hear ya on get bitched out by customers. I was a tech for 10 yrs, 10 yrs ago, I don't miss it at all. But that's why I think you should CYA by doing a alignment properly. This includes checking the rear suspension components that not every tech checks. Wore out rear LCA bushings WILL throw out your alignment. A bent or wore out PHB will do the same.

OP check these things out for curiosity.

StreetLethal

Thanks for the input. I suppose the reason I care is because:
-Initially it was driving significantly off track, then after bringing it back the adjusted it so I wouldn't have to correct with the wheel so much
-I knew the car had some body work done at some point, and have no idea if it was a minor fender bender or a serious accident. I've heard horror stories about guys with cars that couldn't get the alignment right, only to later find out that they had frame damage.
-I don't think the shop screwed up my car at all, I was just curious if it revealed anything about the accident history with it being slightly off.