Could the right brake pull be something other than calipers?

[Old Account - 243]

My right brake pull has returned in the last few days. Same as before, 35mph, hands off the wheel, hit the brakes and the steering wheel turns a full revolution to the right. Adjusting the rear brakes has no effect at all when the pull is this bad so I believe it’s entirely a problem with the front braking system.

I am not an engineer but am trying to use some common sense to figure this out. Please feel free to join in on the discussion.

If the drivers side caliper piston is sticking, it will not clamp the pads to the rotor which will let the passenger side caliper do all the work (True or False). If it is true, the passenger side caliper will pull the truck to the right. If the drivers side caliper piston were stuck while withdrawn in the caliper, it would have to be very tight to not be dislodged by the hydraulic brake pressure (True or False). If the caliper piston was stuck while extended, it would wear the pads out quite fast; or, create quite a bit of heat which could be felt at the wheel (True or False).

Dirty or dry caliper mounting pins is the second possibility. However, the caliper only has to slide fractions of an inch along these pins each time the brakes are applied (True or False).

Sticking caliper pistons or dry caliper mounting pins has been the most talked about problem. It seems odd that the right pull on my truck has happened with the factory calipers and pads, factory calipers and Performance Friction pads, aftermarket calipers and pads; and most recently, Raybestos calipers and pads.

Could the problem really be line pressure to each caliper?

Is there a valve in the master cylinder or elsewhere in the braking system that could be sticking (or has failed) which would cause the drivers side caliper to not clamp properly?

Is the RWAL brake system completely separate from the front brake system?

If it is not, if the RWAL system is faulty, could this cause the problem with the front braking system?

If we could switch the lines going to the front brakes and induce a left brake pull, would this eliminate the sticking caliper theory?

Lots of questions and no answers…

243

------------------
99 QC 2500 ST 4X4 SB 24V/5speed 3. 54/LSD Driftwood/Agate
Walker 21468, VDO, Bridgestone 285/75/16 MT's, RS9000's, Hella 500's

cummins_isb@hotmail.com



[This message has been edited by 243 (edited 01-03-2001). ]

 

[Jetson]

Too many questions for me. But, if the driver's side caliper is sticking, it would not be releasing. This would overheat the driver's side pads and they would not help slow down the truck, just like an overheated clutch pad slips when too hot. This would cause a pull to the opposite side. A strong pull like you are talking about also makes me wonder about looseness in the front end. If applying the brakes caused one wheel to move back because of slop, it would pull. The line pressure thing may be a problem. Maybe you could test it with the guages from a couple redneck boost modules. If you could find a way to screw them into the bleeders and have someone crawl under the truck when you apply the brakes. (I'm not volunteering, but I due have a couple pressure guages) This seems to be more of a 4 x 4 problem, just like wandering. I'm knocking on wood since my 4 x 2 has neither so far.

------------------
99 2500 QC, LWB, 5spd, 3. 54 limited slip, Intense Blue, 275HP Injectors
Tow Lite trailer
96 KTM 360 EXC
99 Durango 4x4 360cid

 

[TowPro]

Not sure which was a truck will pull when a calaper freezes. I remember when Ford trucks were having the problem, It was easy to diagnoss because the brakes would be worn down to the metal, and rotor warn through almost to the fins. When you try to retract the calaper with a "C" clamp it would be real hard to move.

I know on my truck, I found a bad ridge on the calaper where it was sitting on the slide. A file cleaned this up. I use Anti Seeze on my slides and have had good luck. But still the RS inner pad wears faster then the rest of them. Almost 2:1.

Was'nt there a TSB where they were adding a thin spacer between the RF wheel and rotor to stop brake pull?

My pull is not as bad as others here have said. When I stop hard, my wheel will only turn about 1/4 turn.

Next spring, my plans are to install 2 new calapers (make sure they fit tight in the slides, I have heard on this board of remanafactured calapers that are real sloppy when there laying on the slides).

I also plan to install the 3500 wheel cylenders on the back.

------------------

• 98 ISB,QC,5spd,2wd,3:54lsd. Stock with Gauges! (and BD brake this weekend)
• 2000 Terry 305G 5th wheel

 

[WCrovo]

How about **** poor design. One of our moderators has some interesting ideas on spring stiffners. You may have to hunt for it is was recently. Did it when he blew his P/S pump.

------------------
2001 2500 tow, camper, SWB, ETH, Bright white.

 

[WCrovo]

One or two more things. I never liked the way the factory T'd the front brake lines on my 99. I also don't like the huge, lumbering puck on the pre 2000's. I would, if I had kept it would of re-engineered the front flex hoses first and then figured out a way to put different calipers on. MHO.

------------------
2001 2500 tow, camper, SWB, ETH, Bright white.

 

[TradedV-10foraCummins]

One more thought. Most of the trucks don't have matched springs on the front. Almost all of them have a stiffer spring on the driver's side. For example, my 99 is a 4wd QC LB. My left front spring is a #46 and my right front is a #39. I don't remember the exact numbers, but I think there is a little more than 100lb difference in the spring rates. What do you think? This would seem to be supported some by Mark's findings.

 

[Old Account - 243]

I talked to Steve at Dynatrac this afternoon to see if they had information about upgrading the calipers to the dual piston F450’s like Dave Fritz did. When I explained why, the first thing Steve said was, “it sounds like the pressure to each caliper is different, not the calipers themselves”.

A buddy at work said the same thing as well as suggesting that it could be kinked brake lines or trash in the master cylinder. This seem unlikely when so many people have the right hand brake pull.

Walter probably has it nailed, “crappy design”.

I think it may be possible to switch the lines to the left and right calipers at the master cylinder. I will look at that this evening.

Anyone know what pressure the brake system operates at?

It would be easy to install a gauge at the caliper to check the pressure. I would need to know what size gauge to get though.

243

 

[wrench]

I would check very carefully the flex hose,,some guy squeeze them with wisegrip when replacing caliper and damage the iner liner,or a twisted hose. The rubber will partialy clog the hose creating a differential pressure between both side, and pulling on the side with the higher pressure. To check it, open the bleeder & observe the flow of oil as an assistant slam a good shot at the brake pedal, one side at the time, the one with the smaller flow is cloged, replace both.
good luck
Wrench

------------------
If it's smell fuel, bring it over!!

 

[MDW]

Same problem here #ad


------------------
95' 2500 standard trans. 2wd reg cab 125,000 miles.
TST #4 plate kit, 370 Diamond B injectors, Afc spring kit, Gov. spring kit,TST's fuel pressure adapter and 2 guage pillar mount, SPA EGT/Boost guage. Joe D's Sachs clutch is in.

 

[NVR FNSH]

Somebody care to enlighten me as to what a good brake design is versus 'crappy' design? I really can't stand it when blanket statements are made with no basis presented.

anybody hearing complaints about brake pull from drivers of Jeep Grand Cherokees or TJs - they have the same front suspension design?

As far as the spring rate theory:
My '79 CJ-7 has the same rate leaf springs on each side of the front axle - leans like the Titanic to the driver side w/me in it - no brake pull to either side. A lot of vehicles use different rate springs on each side w/o brake pull - kinda makes me wonder...

Here's my list of culprits -
hung caliper piston
stuck/sticky caliper bracket slide
pressure differential between the calipers

Brian

[This message has been edited by Brian Meadows (edited 01-04-2001). ]

 

[Dane]

I think there is a BIG clue on my truck. I have noticed the right front wheel shows much more brake dust than the left front. I don't yet have any brake pull, but I believe there is a design flaw causing the right front pads to drag more than the left. This over time will cause the left and right side pads to be different thickness and a difference in the left and right rotor and pad surfaces. This would cause brake pull. If so, changing the pads and surfacing the rotors should fix the problem for a time.

------------------
2001 HO 6 speed Regular Cab SLT 4x4 3. 54 anti spin 2500. Used for the daily grind and sneaking away to some secret Baja beaches toting a cabover

 

[Old Account - 243]

Brian-

Does the Grand Cherokee use the power steering pump for power brake assist?

243

 

[Old Account - 243]

Walter-

What is a "puck" and can you elaborate on redesigning the flex hoses?

243

 

[NVR FNSH]

243,
I don't know if the GC use the common power steering/brake boost set up. I believe that that GC's use vacuum from the engine for the power brake diaphragm

Brian

 

[Josparkz]

The last time mine did the powerbrake/pull, a good alignment corrected it, with installation of caster/camber bushings on top of the steering knuckles.

------------------
"Roadrunner"-96 4X4 club cab-12v-auto-3. 54 gears-Amsoil bypass filter - all Amsoil fluids-trans filter-britebox-shelfit-DeeZee boards-Rhino liner-Rancho 5 speed shocks-Hellwig rear antisway & overload springs-Warn 12000 lb. winch-dual redtop optimas-combo gauge and trans. temp gauge in pillar mount-255/85R16 Kelly MSR tires-custom pinstriping- Walker muffler-Cummins mudflaps-Tuff Country control arms-2" coil spacers

 

[zzman]

I do not have the pull of the steering wheel, but I do have a touchy left rear. The first time I brake, it locks up.
I think it may be the parking brake cable sticking. Will check it when it dries up here.
243 it sounds like you may have a kinked line. Maybe the line to the "left" side is of a larger diameter than the right. May be something it the line.
If many have the same problem, I would look at the entire line from master to wheel. I would feel the factory used a bad tee or connections. I'd wouldn't surprise me if there was a spot that is pinched from front-end turning.
Good luck, keep us posted.

------------------
97 3500 dually, ext. cab p/u,5sp,2wd,3:54,245/75R16,
straight pipe,105k mi.
Ron

 

[Joseph Donnelly]

Modest cases of brake pull may be ixed by going to Performance Friction pads. I got a bit of pull sometimes when the pads were nearly worn out, too.

Remove the bottom rubber plugs from the rear brake backing plates, insert a screwdriver, and crape off some of the black crud from the side of the brake shoes. If it is oily black crud, you have a seal leaking. That will cause a lot of brake pull. Substantial difference in brake adjustment side to side in the rear will also contribute.

 

[Old Account - 243]

I have not found an easy way to swap the front brake lines. I am going to try checking the fluid pressure at each caliper but I need a gauge and some fittings.

Anyone know what the typical operating pressure of a brake system is?

Why do brake caliper pins use a rubber bushing instead of a bronze bushing?

243