Front brake pulling left

[steve miller]

Hello all. I have a problem that I just can’t figure out. When I bought the truck someone had put line lock on it. I removed the line lock and was having my driver side caliper hang up. I replaced the caliber, rotors and pads. It did it again! I replaced the porportionong valve. It did it again! I thought it might be the module that controls the ABS so I bypassed it. Replaced the master cylinder, all front brake lines and got rid of the porportiong valve and installed a Wilwood. It is STILL pulling to the left. I can tell that the driver side caliper is the only one getting fluid. I will upload a pic. As it is currently it comes off the master cylinder, goes to the wilwood proportioning valve which has two outputs for the front and one to rear. Any help is GREATLY appreciated!

 

[AH64ID]

What have you done on the passenger side?

 

[Joe Mc]

Typically it's best to replace both front (or rear) calipers. That said, get a pressure gauge and connect to the bleed port each side (sorry I don't know what psi should be? I'm guessing somewhere around 800#, check online) with engine running press on stop pedal and hold a few seconds, have someone note psi. Switch side, repeat then compare. Oh, make sure psi returns to 0# after you let off pedal. I had a hose fail internally, rubber created a flap making a check valve. Keep us posted.

 

[BigPapa]

get a pressure gauge and connect to the bleed port each side

Don’t think that’s going to work, Joe. The bleeder screw has no way to connect anything to it, especially that will handle 800psi. The only way I can think of to connect a gauge would be a longer banjo bolt and another fitting for the gauge. I don’t see any spec anywhere for brake fluid pressure. I’ve never heard of someone checking brake fluid pressure, either it has pressure or it don’t.

I’m a bit confused as to what’s been replaced. Have both calipers and both hoses been replaced?Is it four wheel ABS? Has it been bled properly?

 

[Cummins12V98]

Replace hoses.

 

[Joe Mc]

BigPapa, I've never done it myself but have seen it done before. Here's a kit
https://www.speedwaymotors.com/Brak...8890847&utm_content=All Products (Feb28_2020)

and here's a how to, with brief on what you might find wrong

https://www.motortrend.com/how-to/check-brake-system-pressure/

Hope this helps somehow.

 

[Ozymandias]

From what I read he replaced all and everything more then once to solve it and nothing helped.

 

[AH64ID]

He said he replaced the caliper, not calipers. That’s why I asked about passenger side stuff. If that caliper wasn’t replaced it could be an issue.

It could also be a blockage to the passenger side causing it to pull left.

He also didn’t say if it pulled when braking or when not braking. The original post sounds like both, but that’s not super common for brake related pulling.

 

[Ozymandias]

If the rear left binds, or the right is dysfunctional it also pulls to the left, nit so strong as a front one but can be felt to. That's how ESP works.

 

[GAmes]

Sometimes pull is caused by a malfunctioning REAR brake. Last year I had a rear seal leaking, not enough to be visible on the inside of the tire, but just enough to keep the brake shoes saturated. Hard braking would cause a pull to that side.

 

[Joe Mc]

Steve, Have you figured anything out yet?

We'd like to help. Sometimes it's the simplest thing, sometimes it's not. We need some more info:
1- Does it pull to the left "all the time" or "only when braking"?
2- From your pictures it appears you have RWABS (rear only Anti-lock), yes?
3- What year is your truck?
4- Is it 4X4 or rear wheel drive only?
5- Is the brake system (outside of the Wilwood proportioning valve) stock?

As others mentioned a pull can be related to the rear brakes = leaking axel seal or wheel cylinder, soaked shoes (assuming rear drums). Or even a bad rear wheel cylinder/caliper. As well as a myriad or other things.

A tip to help folks help you whit out all the questions = what year, auto or stick, 4X4, and etc., every time you start a thread or reply to one.
Go to the upper right of the window, hover (don't click) the cursor over your name, you'll see a dropdown appear, on the left 2nd item down, you'll see "Signature", click on it and you'll be taken to where you can list such things as those people will ask. Saves time for you and others, also where you can list modifications and whatever.

I hope you're figuring things out with the brakes. Please let us know how you're making out, to not, the things you (we all) figure out and share with each other helps everyone.

 

[Cummins12V98]

On my 01 Sport the rear long steel line with rubber hose at end was BAD. Dealer ONLY and it was $$$.

 

[steve miller]

Hello all, thank you So so much for all the help! Truck is a 98 4x4 auto. I replaced all calipers and all new lines with stainless hoses on the end. It has rear ABS only. The truck came from the factory with drum brakes on the back but somebody swapped it over to disc brake conversion. It seems like the rear calipers were off of Chevrolet used in a conversion kit. The rear calipers and front are all new though. The truck pulls hard left only when the brakes are applied. Thanks so much!

 

[Joe Mc]

Steve, this info helps, thanks. Years back I converted to rear disc with a kit from Blackbirds Custom Trucks (Not sure if they're still around, tried search and results were???) anyhow, I went with the E-brake type kit and the rear calipers are from a 76 - 78 Eldorado (rear), the drums are from a Chevy 2500 and the hoses were from a Dodge 1500 front. Hard to tell if the kit on your truck is the same, just provided info in the event you might need rear pads, etc., at some point. Doubt the kit is related to your issue, though.

Your description; 1- "hard pull left only when brakes applied", 2- "replaced all calipers with new" and 3- "all new lines with stainless hoses" - helps and brings a few thoughts to my old head.
1- It appears that the front left caliper is doing all the work (at the front) Duh, right... Weird set up for the front lines. You replaced "all lines", I believe the line from the block in the left wheelhouse area runs 1-to the left and 2- to the right side along the firewall behind the engine (could be wrong and my truck is in the body shop now) if you replaced this line, or not, is it possible it is/got kinked?
2- "replaced all calipers with new" - Assuming the calipers are remans. One thing reman outfits don't do, that I've noticed, is resurface the caliper slides (where they land on the caliper mounts). If the flat areas on the slides, both on the caliper and the mount, have imperfections = dings, low/high spots and are not lubed (Sli-glide or whatever you use on the caliper bolt/pins) this can cause a caliper to stick or not fully return to the "off brake" location. Before installing new (reman) calipers clean the caliper mount/bracket and inspect for any imperfections if you find them flatten them down (across the flat face) with a smooth file, pay special attention to the rounded areas along the sides and the leading edges. You'll want them to be just smooth, don't try to speed things up by using a sanding disc, just file. Do the same with the flats on the calipers. Apply a light coat of lube to both surfaces before installing, don't over do it, just a real thin coat.
3- "all new lines with 'stainless hoses'" - assuming you used braided stainless hoses from the hard line to the calipers. Even though new there could be a defect, rare but possible. If a internal hose failure (a flap of rubber) is present it will create a check (one way) valve which can reduce/stop flow either into, or out of, the caliper. Only way, without disassembling the whole works, to try to figure this out is to get someone to help. Both front wheels off the ground, apply and release brakes, quickly see if both wheels turn freely. Turning the right front wheel apply light pedal pressure to the point where you feel the brakes begin to grab - leave foot in same position on the brake pedal - go to the left front and see if it too is turning or locked. If left front is locked, release pedal, turn the left wheel as light pedal pressure is applied to the point where you feel the brake begin to grab - leave foot in same position - go to the right side and see if it is free or less than left side.

What a pain in the arse! OMG! brakes aren't supposed to be so darned complicated, right! Yes, and they aren't until they don't work right...

Thoughts: Either the left front caliper isn't releasing all the way or the right front isn't applying. The dilemma is figuring out why? No fluid getting to right, too much to the left, stuck caliper (on one of the slides), kinked line, failed hose, restriction between left and right?

This is really driving me nuts, I feel your frustration and wish I could be there to help try and figure it out.

Hope some of the above helps somehow. Sorry.

Please keep us posted. Good luck and try to have some fun in your troubleshooting. Remember when you figure it out it'll be great and even better when you share the fix with folks here. Chin up buddy.

 

[MGreer]

You said you are certain the drivers side caliper is the only one getting fluid. Loosen the line at the passenger side caliper and have a helper push the brake pedal down to see if any fluid is there. If there is a good amount of fluid you probably have a bad caliper on that side, if there isn't any fluid at the caliper loosen the line/hose connections one at a time back to the master cylinder and you should be able to determine where the blockage is.
The biggest restriction is the mounting bracket on the frame the rubber hose mounts to. Rust builds up on the inside of the bracket and squeezes the hose shut. You can bend the bracket enough to pull the hose out and clean/determine if thats the issue. I just had to do this on our 2015 jeep wrangler.

 

[Joe Mc]

MGreer, Never thought of that, awesome! Got to love this site.

 

[steve miller]

A little update. I ordered a brake test gauge from JEGS to test pressure at each caliper. As soon as it gets here I’ll post an update. Thanks for the help!

 

[Matt42]

A little update. I ordered a brake test gauge from JEGS to test pressure at each caliper. As soon as it gets here I’ll post an update. Thanks for the help!

I will be watching for your results. I'd also like to see a pictorial of how you set up the gauge.

 

[Freakonabike]

I’ve got a 99 2500 4x4 with the same problem. Was told it’s the cam gear on the suspension. One on the left and one on the right, bottom track bar at the front. They’re supposed to be off by each other and not on the same marks. Most alignment shops make them even which causes your truck to pull right or left. I haven’t adjust mine yet, I’m on vacation. But try offsetting them one mark from each other and see if it fixes it or makes it worse. If worse, adjust the other way and see if it works.

 

[petersonj]

Was told it’s the cam gear on the suspension. One on the left and one on the right, bottom track bar at the front. They’re supposed to be off by each other and not on the same marks. Most alignment shops make them even which causes your truck to pull right or left.

From what you are describing, this sounds like caster adjustment. Caster adjustment would not be relevant to a vehicle pulling to one side or the other only when braking. Caster is typically adjusted using two preferred methods.

One method allows the vehicle to track straight ahead if the roadway is level (neither sloped to the left or the right). If the road is crowned to the right, the vehicle will lightly drift to the right. Caster is adjusted evenly on each side using this method.

The other method compensates for road crown (usually sloping to the right) and allows the vehicle to drive straight ahead on roads crowned to the right. Caster is adjusted unequally using this method.

- John