Truck Pulls To The Right

jblakeney · October 3, 2011

Here's another weird thing to ask. If you hit the brakes hard does it multiply the pull? or stay the same?

Jbo

1990ss · October 3, 2011

I rotated the tires this morning, haven't had a chance to drive it yet, but I will be here in a little bit. I'll try hitting the brakes and turning the engine off also if it's not the tires.

1990ss · October 4, 2011

Well, I rotated the tires and it still pulls. I also tried hitting the brakes; no difference. Shut the engine down; no difference. Tie rod ends and ball joints look good. I did notice that on somewhat flat roads, it actually drove straight, but if it hit the slightest bump, it went right pretty hard. On the crowned roads, it doesn't even think about going straight. Could it be that the alignment is still off? Or is there something else to check?

ChevyTech77 · October 4, 2011

Has to be in the wheel alignment. What are the current settings?

1990ss · October 4, 2011

Not sure what the settings are. Don't know much about wheel alignment. Is there a way to see what they are, or is that something the alignment shop would have to tell me?

ifshinxs · October 4, 2011

Not sure what the settings are. Don't know much about wheel alignment. Is there a way to see what they are, or is that something the alignment shop would have to tell me?

Sounds like the castor needs to be adjusted until your pull goes away. Which in your case may mean that your alignment may have to be set OUT of specs to acheive a straight running truck.

ChevyTech77 · October 4, 2011

Not sure what the settings are. Don't know much about wheel alignment. Is there a way to see what they are, or is that something the alignment shop would have to tell me?

Did they give you a print out of what they set it to? Does it say on your reciept somewhere? I've done wheel alignments for nearly 20 years and always put the wheel alignment settings (of what I set it to) on thier repair order weather it was a printout or hand written.

ChevyTech77 · October 4, 2011

Sounds like the castor needs to be adjusted until your pull goes away. Which in your case may mean that your alignment may have to be set OUT of specs to acheive a straight running truck.

I've never had a vehicle that I couldn't get to drive straight and keep it within manufacture's allowed specifications. Even repaired vehicles.

pm26 · October 4, 2011

The alignment setting that can cause pulling to the side is caster. It is purposely set unequally on both sides to compensate for the crown in the road. The guy doing the alignment should have experimented with several caster settings within the specification range to get rid of the pull.

Sometimes a bad tire can cause the vehicle to drift, not necessarily pull hard. I had this happen on a passenger car.

Also, unequal camber settings can cause a pull to the side, i.e if one wheel has positive camber and the other negative or neutral camber. Bopth wheels should have the same camber setting (slightly positive).

Improper toe setting typically does nto cause pulling to one side, only feathering of the tire edges. Both wheels should have the same toe setting (slightly positive).

My advice is take the truck to another place that knows how to do alignment properly.

As mentioned, I would carefully inspect front calipers for any possbility of dragging on the rotor. An old rubber brake hose can cause this, as it swells internally and acts as a one way check valve. I had this happen on an older GM car and it was incredible how badly the caliper dragged on the rotor. Replacing the caliper did nothing, replacing the brake hose fixed it.

ChevyTech77 · October 4, 2011

The alignment setting that can cause pulling to the side is caster. It is purposely set unequally on both sides to compensate for the crown in the road. The guy doing the alignment should have experimented with several caster settings within the specification range to get rid of the pull.

Sometimes a bad tire can cause the vehicle to drift, not necessarily pull hard. I had this happen on a passenger car.

Also, unequal camber settings can cause a pull to the side, i.e if one wheel has positive camber and the other negative or neutral camber. Bopth wheels should have the same camber setting (slightly positive).

Improper toe setting typically does nto cause pulling to one side, only feathering of the tire edges. Both wheels should have the same toe setting (slightly positive).

My advice is take the truck to another place that knows how to do alignment properly.

As mentioned, I would carefully inspect front calipers for any possbility of dragging on the rotor. An old rubber brake hose can cause this, as it swells internally and acts as a one way check valve. I had this happen on an older GM car and it was incredible how badly the caliper dragged on the rotor. Replacing the caliper did nothing, replacing the brake hose fixed it.

Camber and Caster can equally make a vehicle pull. Caster just won't wear your tires.

Camber on this vehicle is set slightly negitive, like most all newer vehicles are.

I've had a tire that would pull you just as hard into the ditch as poor alignment setting would.

Oddly enough, I've had a very far off toe setting do the same thing.

Lots of things going on with just a pull concern but considering that the OP has replaced tires, rotated tires, no measureable brake drag and has no pull with the engine off, I'm laying my money on incorrect wheel alignment settings.

1990ss · October 4, 2011

Thanks guys for all the info. I'll take it somewhere else to get the alignment checked.

ifshinxs · October 5, 2011

"The alignment setting that can cause pulling to the side is caster. It is purposely set unequally on both sides to compensate for the crown in the road. The guy doing the alignment should have experimented with several caster settings within the specification range to get rid of the pull. "

Perfectly stated. Sometimes you have to think (Adjust) outside of the box...Adjust and drive, adjust and drive until you find what works.

1990ss · October 5, 2011

Is the caster something I can adjust myself? If so, how do I adjust it? Will it affect tire wear?

ujtruck · October 5, 2011

you have a bad front calipers (passenger side) - how do i know this? I have - same issue, if you can pull all your front brake pads out, you'll see uneven wear

pm26 · October 5, 2011

Is the caster something I can adjust myself? If so, how do I adjust it? Will it affect tire wear?

No, you need an alignment machine for that. The settings must be accurate to a fraction of a degree. And no, improper caster settings by themselves do not affect the tire wear because one wheel is slightly ahead of the other and the tire tread contact angle with the road is not affected. Excessively positive or negative camber causes uneven tire contact with the ground, and tire edges wear excessively. Excessive toe in or toe out will result in tire edges getting feathered (tire scrubbing action).