What causes out of round REAR tires? Alignment sheet inside!

[craven]

i have a chassis shop looking at it monday and if its an axle they will replace it, and if its the tube they will straighten it....

now considering i am +.56 degree toe on passenger and -.08 degree toe on driver side...thrust angle is +.19 degrees...

now that being said even if they straigten out the passenger sideto be close to 0 degrees or even -.08 so the axle is completely straight, which they most likely will!

that means after i correct the +.19 degrees thrust back to 0 degrees my toe will be -.25 degrees on each side....is this bad?

axle should straight by then, but i have a feeling the toe on the drivers side should be +.15 or so, and when the axle goes in on the passenger it will probably be close to same, giving me a near 0 degree toe once thrust is fixed....

BUT is adjustable lower control arms more effective than relocation brackets for fixing thrust? if so what is the reloaction brackets for?

 

[1lowtoy]

Total toe is what is so bad. If you end up with -0.25 on both sides, thats a total toe of -0.50, thats bad. You (more than likely) will never see a total toe on the a straight axle rear right at zero, but you should be close. If you are at +0.10 on the right and -0.10 on the left, then you could adjust the lower control arms for the thrust angle and be good. If you are taking it to a good chassis shop, then you should have nothing else to worry about.

 

[craven]

Total toe is what is so bad. If you end up with -0.25 on both sides, thats a total toe of -0.50, thats bad. You (more than likely) will never see a total toe on the a straight axle rear right at zero, but you should be close. If you are at +0.10 on the right and -0.10 on the left, then you could adjust the lower control arms for the thrust angle and be good. If you are taking it to a good chassis shop, then you should have nothing else to worry about.

yea i am taking it to Tim Bradshaw, the best chassis shop in the traingle NC......

so i guess i am good....

 

[craven]

what about bent or warped rims? cause i took the tire off and it didnt look like the hub was moving....

 

[NastyStang113]

what about bent or warped rims? cause i took the tire off and it didnt look like the hub was moving....

I think you would notice if the wheel was bent. If it was bent enough to cause what's showing up on the alignment than it'd be really bent!

 

[craven]

ok...was just wondering.....

 

[craven]

well some good news for me, i just found out when my new tires were put on that my passenger rear rim is bent, enough so it called for a good amount of weight, well thats the tire that had the most uneven wear and bad toe angle on the alignment rack...

thats also the spot that was hit, and which most likely bent the rim....the tire and alignment specialist said that the uneven wear on the passenger rear tire is caused by a bent rim that isnt balanced and hops at higher speeds instead of rotating...

and they checked and the rims were not balanced properly, and enough to cause it....so they balanced the new tires on the rims perfectly and got them zero'd out on weight completely even the bent rim, he said the bent rim will be ok now because he was able to balance it...

the rear end is so much smoother, and accelerates better, i cant explain it, just feels soo smooth!!

so i guess all is good now, the tire specialist is going to do an alignment check with the bent rim on passenger rear like it is, and then move the bent rim to the driver side rear....and re check alignment...

if the toe is only bad where the rim goes, then its just the rim.,..and most likely is.!!!

 

[Sinotis]

Most alignment machines compensate for slightly bent rims. I don't think a bent rim is causing your issue unless your rim is badly bent like someone else said.

 

[craven]

Most alignment machines compensate for slightly bent rims. I don't think a bent rim is causing your issue unless your rim is badly bent like someone else said.

its definately bent, and a bent rim can cause uneven tire wear too....

 

[1lowtoy]

Did the wheel have the side to side movement while mounted on the balancer? I'll bet that it didn't. It may be bent and that could cause uneven tire wear (tire wear should be different 180 degrees from the bent spot, not just wearing the whole inside or outside edge of the tire). What did the chassis shop have to say or did you not take it to them?

 

[craven]

Did the wheel have the side to side movement while mounted on the balancer? I'll bet that it didn't. It may be bent and that could cause uneven tire wear (tire wear should be different 180 degrees from the bent spot, not just wearing the whole inside or outside edge of the tire). What did the chassis shop have to say or did you not take it to them?

i put the new tire and rim on the axle and lifted the car, and let the wheels spin, the passenger rear looks the same as the rim does on the alignment machine, slight side to side movement...

the reason the old tires moved more is because the tread was uneven and the rear tires were not balanced at all....

but right now the rim moves back and forth on the balancer....not a whole lot but about the same as when its on the axle....

 

[limelight]

So are you replacing the bent rim then?

 

[Sinotis]

There are a couple of things that don't make sense here. First of all you said the people that you took it to the first time said your rear end was good. Its not good. Second of all an unbalanced rim and tire has nothing to do with tire wear. The amount of weight you put on a rim has nothing to do with a rim being bent. ALL bent rims can be zero balanced so there is no miracle here. Your car rides smoother because they were able to position the tire on the rim in a way that decreased the road force of that tire. You also said the passenger side rear rim was chopped on the inside edges. This is caused by your right rear toe setting. The rim being bent has not caused your alignment issue and your inside tread to be chopped. When your car was hit it tweaked or bent more then just your rim but if the car drives straight and there is no vibrations then just drive your car and enjoy. No sense in replacing the bent rim if it doesn't hop but if you don't get the rear end straightend out you new tires will become chopped and start hopping again very soon.

 

[Bryan@suttonhp]

I havent read every post so i dont know if it has been covered or not but when you lower the car it wants to go to one side, Alot of guys are throwing panhard bars to adjust this problem.

 

[1lowtoy]

There are a couple of things that don't make sense here. First of all you said the people that you took it to the first time said your rear end was good. Its not good. Second of all an unbalanced rim and tire has nothing to do with tire wear. The amount of weight you put on a rim has nothing to do with a rim being bent. ALL bent rims can be zero balanced so there is no miracle here. Your car rides smoother because they were able to position the tire on the rim in a way that decreased the road force of that tire. You also said the passenger side rear rim was chopped on the inside edges. This is caused by your right rear toe setting. The rim being bent has not caused your alignment issue and your inside tread to be chopped. When your car was hit it tweaked or bent more then just your rim but if the car drives straight and there is no vibrations then just drive your car and enjoy. No sense in replacing the bent rim if it doesn't hop but if you don't get the rear end straightend out you new tires will become chopped and start hopping again very soon.

Amen brother!

 

[1lowtoy]

I havent read every post so i dont know if it has been covered or not but when you lower the car it wants to go to one side, Alot of guys are throwing panhard bars to adjust this problem.

Very true, but this has nothing to do with tire wear.