Vehicle pulls left or right when braking

[Matahoe]

My 2005 Tahoe LT 4x4 seems possessed. Does anyone know what would cause the vehicle to pull randomly to either side when braking only? I realize that the primary cause is usually a bad caliper but if it randomly pulls to the left or right...what would that be caused by? It's very odd behavior and in 30+ years since working on gm vehicles I have never seen this. It's always been to one side or the other!

All my steering and suspension components are new other than the shocks. The front shocks are used off a esky with 60k. It's been an additional 10k since installing them.

I have noticed my body is starting to lean when turning. Perhaps my rear shocks need replacement? They are Arnott reman'd z55 air shocks installed by previous owner in 2012

Proportioning valve is front to back and not left to right. Same basic principle for the master cylinder. The only thing that I can think of is bad front shocks. But if I can feel it in the steering wheel pull as well...it must be brake related.Correct?

Thanks for any help. I am prepared to buy another set of Arnotts just because I think it's time. They may solve the issue but I hate throwing parts at a problem and hoping for a change. I need this solved asap as this seems like a safety issue.

 

[wjburken]

Interesting.

When was the last time you had the alignment checked?

Does it pulse when you hit the brakes?

Does it get better or worse with the speed you’re going when you first apply the brakes?

If you ease into the brake pedal vs stomping on it make a difference?

Have you checked the level of your brake fluid?

What do your brake lines look like? Are they original?

 

[OR VietVet]

Yea, check the brakes obviously for peace of mind and look for mount problems with calipers and any problems with the fluid lines, front to rear. The first thing I thought of was steering or suspension problems and ride height is important so get that lean looked at. Sway bars and shock mounts and anything at all need to be looked at. Maybe after all the new steering and suspension parts there is something coming loose. But what I first thought of is the alignment. Was it aligned after the new parts and you should have gotten a print out of the before and after settings. Please post that info here.

Also look for any engine or trans mount problems and axle mount problems. Leave no stone unturned.

 

[Matahoe]

Alignment was just done. I had Discount Tire put on Michelin LT tires last year. They are inflated to 55 psi. Vehicle drives straight all over town and on highway. I need to make it clear that the vehicle only pulls when braking. I'm thinking maybe air in or near the master cylinder, boost pump or ABS modulator valve? Logically though that wouldn't explain the left or right pull however.

 

[OR VietVet]

I would want to see the before and after specs of the alignment anyway but if you are satisfied, so be it. Plus, are you sure all tire pressures are even? Just throwing out possibilities to see what sticks. Been surprised many times in the past when I assumed. Since we can't drive it you have to be our eyes and ears.

 

[Matahoe]

Understood.The really odd thing about this behavior is the lack of similar cases when performing a Google search. It's almost as if my symptoms are unique.

Something that may be of use....I was in an accident 5 years ago. I pulled into the right lane and a minivan hit my right wheel and destroyed the inner and outer tie rod and wheel. It's since been fixed. I am curious if maybe my steering gear or center link would cause this? I'm just grasping at straws for a lead at this point.

How important is geometry of frame/ steering/ braking components when trying to solve random pulls to the left or right? I would think there would be no ambiguity in this case.

 

[OR VietVet]

You said this: "All my steering and suspension components are new other than the shocks. The front shocks are used off a esky with 60k. It's been an additional 10k since installing them."

In the initial post I would have led with this info about the wreck. In the above statement you said ALL steering and suspension components are new. I am curious now as to whether the center link was replaced during this statement and if the steering gear was also replaced related to this statement. When you say everything, I am going to accept what you say and make decisions from there and the wreck part I feel is very important to know about as well. You may have frame damage from the wreck, have a frame misaligment from the wreck, a damaged engine mount.....any number of things. I am sorry for your problems but COMPLETE info is a must.

Were the wreck related side control arms and bushings replaced and ball joints? If you could, could you please list EVERY steering and suspension component replaced since the wreck and provide alignment readings? This jumping side to side when braking is dangerous and we should leave no stone unturned.

 

[Matahoe]

Also look for any engine or trans mount problems and axle mount problems. Leave no stone unturned.

I have little experience with these items. Not seeing how they would coincide or work against braking.

However! I have since called my insurance company. There may be major structural damage unseen at play here (I.e cracked frame, broken engine mount or suspension pivot point). Point being...I may have been played when the body shop sub'd out the steering and realignment work.

 

[OR VietVet]

Needs checked by a pro that knows what they are doing and what to look for.

 

[swathdiver]

My 2005 Tahoe LT 4x4 seems possessed. Does anyone know what would cause the vehicle to pull randomly to either side when braking only?

Yeah, take your hands off the steering wheel next time Matt! hehehehe

Like a 4x4 launch at the drag strip or a crash stop, I've seen the tie rods give way and cause the wheels to wobble. Bad ball joints too but to a lesser extent. I would still start with the calipers and brake hoses and then test the tie rods. Then the master cylinder.

https://www.powernationtv.com/post/truck-techs-supermax-could-be-your-next-truck