UBJ Blown and outer tire wear. OME 881 & 5100. What gives? (Was Front End & Brake Conundrum.)

Jump to page 5, post #82 for the latest issues. Much work was done in 2019 and now in 2021 i have a blown UBJ and bad outer tire wear.

Running OME 881, 5100 set to Zero (I think), 1" levelers with OME 5 pack in rear. 265/75R16 tires. All stock otherwise and all replaced back in 2019.



Below here is the start of the old 2019 thread.

Need some help.

My truck
2004 Tacoma Double Cab. 175K miles. V6, AT with 4x4 conversion. (J-shift & Manual locking hubs.) I have rebuild almost everything.

The problem
At almost any speed i pull left. Not dangerous but enough. At all speeds as i press the brake peddle the steering wheel first goes slightly right and then left. There is no apparent drift right but i do pull left. At slow speed you can tell the right brake hits first and then the left.

What i have done.
- All new ball joints.
- New UCA
- New LCA bushings & adjusters
- New inner & outer steering rod ends
- New steering rack urethane bushings.
- New flexible brake lines front & rear.
- New front brake calipers, pads, shims & rotors. (Tundra upgrade with Napa & Factory parts)
- New front wheel bearings.
- All new seals on everything.
- Truck has been re-aligned 2 times.
- Tires have ~10K miles on them.
- Flushed brake fluid completely.

More info
- I have tested at all speeds. Always behaves the same.
- I have stopped the truck at various speeds using the emergency brake only. No pull at all.
- The problem existing before i did the Tundra Brake upgrade. The upgrade changed nothing.
- I feel no slop in the steering rack meaning that if i push pull the wheel while in the air or rock the steering while moving it seems tight.

Threads
Past front end help thread.
4x4 build thread.

What am i missing?

 

New Master Cylinder? Are you running the recommended brake fluid and not some racing stuff like dot5.1 ? Are the Tundra calipers brand new or refurbished? they should have fixed the problem but I suspect the Master if you had this issue previous. As alignment goes, toe out can cause it. Laces out Dan Marino lol.

 

Master Cylinder i have not messed with.
I am running standard DOT 3
Tundra Calipers were rebuilt/refurb Napa units.

My knowledge of master cylinders is based on 60's technology so how would a bad modern master cylinder cause this?

Toe in. Hmm. I have a lifetime alignment so i can always get another. I will dig out my results and posts them but they were within spec.

Thank you.

 

Man because you master is weak, so what pressure it has takes the quickest route the the caliper on the same side of truck and just barely has enough for the other side? Far fetched but maybe.
Bad refurb cal?
Soft/weakened suspension on that side allowing it to dive more?
Left side rear shoe adjusted tighter and engaging quicker?

 

Try unplugging the large connector at the ABS module/pump. Then retest drive.
Also find some dirt lot and make the ABS activate. A few hard stops to make it cycle.

 

I will add that there are new coils and struts in the front as well.

I will try the ABS tests.

Thank you

 

Just to get the obvious question out of the way, you got an alignment after all that suspension work right?

I found that after I replaced my UCA’s, the truck would veer. I would have to hold the steering wheel 5 degrees to the left to go straight.

I attribute this to the Camber adjustments that can be made with my SPC UCA’s.

 

@ bartmaster1234. Yes. At least for all the major work involving the UCA, LCA, ball joints, steering inner & outer ball joints, steering rack bushings and front spindles.
I did not re-aligned after installing struts/coil springs but it was pulling before and after the same. (5100 set to zero & OME 881's)

@mechanicjon. A bit of other info relating to ABS. With my 4x4 conversion i took non-ABS, manual locking hubs and installed them into ABS spindles. I am not sure if that matters but might as well air out all the dirty laundry.

@Catcrazed. Master cylinder. I was under the impression that the MC is one cylinder that feeds the front circuit. It applies pressure and that pressure equalizes in as pressure builds until it moves the brake cylinders. I know my older cars have different pressure cylinders for front and rear but the fronts are the same circuit. I guess when the MC goes bad i would not expect that. Am I wrong?

Thanks guys.

 

What I was saying it the line from the master is 4ft river let's says and to get to the pass side 8 ft.
It really shouldn't make a difference but in theory the further away one could get less pressure if there was reduced pressure at the source. Like I said long shot.
I'd suspect abs or faulty caliper.

 

I don’t believe it’s calipers at all if this was pulling before and still doing it after the swap its easy to believe the Master is on its way. I’m sure of it, backed by a family brake and alignment biz that’s been around for 50 years and our techs make over 150k a year, we know brakes, our old school tech Bob Lynn who is a genius agreed that the culprit is the master w/o looking at it. All the front end work doesn’t matter you have calipers grabbing at different times the saying divide and conquer comes to mind, you can rule out all front end work and calipers, as the issue never stopped, think about it.

 

Shouldn't effect it. ABS still work?

 

@Luv my yota. Thank you. Can you help me understand what inside the MC is going on to cause this? I imagine it would be the seals/plunger going bad? Am i talking about a rebuild or replace? Are we talking just the MC or the booster too?

Thank you.

 

Anytime that’s why I’m here!, so with the brake booster go down the fwy get to speed limit and steady the gas pedal and hit the brakes lightly, keep speed as constant to not shift (auto) so what you are gonna do is listen for the truck to idle up while the brake is depressed with the gas pedal steady, if the booster works it will idle up. Do this several times to insure it’s idling up, if so the brake booster is fine and at that point you know it’s the Master Cylinder only. Boosters run on vaccum so you’ll know if it’s not working bye (not) idling up.

 

Since i am heading out on a trip and replacing the MC right now has to wait i did some other testing.

@mechanicjon I tested by removing the large connector on the ABS module under the hood passenger side. No change.

@Luv my yota I will test the booster later. I have no issue replacing the MC but want to test the booster before i do. Could it be the booster only or are you suggesting that the MC for sure and we are only testing if the booster is also in poor shape?

Some other info.

My son reported pulsating in the brakes left/right going downhill only the other day. It seems i have seen that before right after i swapped out the front spindles with the manual locking hub/ABS set-up. Only happened a few times and felt like warped rotors but goes away as soon as your off the downhill. Does that sounds like ABS? Can i test that if it happens again by taking off that same large connector?

 

Could be the booster so just test it as stated to rule it out. Pull the fuse for abs and see if it pulsates still.

 

Doubtful it's ABS. Could just be a hot spot on the rotor grabbing. Did you cycle the ABS in some dirt?

 

Not yet. Will do this coming week.

 

After a 1200 mile trip that included many different driving conditions i have some more clues and test results.

@mechanicjon ABS is not involved. I pulled the fuse and drove down MANY hills with no changes.

@Luv my yota the booster appears to be fine. @ 60MPH when i tap the brakes the RPM rises a few hundred each time tested. I do have a MC rebuild kit on order and will rebuild this weekend.

@BartMaster1234 i checked my last alignment results and all aspects are within the acceptable range according to Pep Boys. But read on please as i suspect something.

Now here is new info.

- Light Trails did not change the effect. Still pulled.
- All the crap i hauled to the mountains made a huge effect. All the weight on the rear end made the pull allot worse. Not dangerous but for sure worse. When i unloaded at the camp site the pull went back to being minor and when we loaded back up to leave it got worse again.
- Both front tires are scrubbing on the outside edge bad and evenly. I would swear they are toed in too much.
- I picked up on a noise i had heard earlier but did not place. When i brake and go over a painted road line i get a squeal from the front wheel every time. Almost like when i brake the wheels are scrubbing and slipping over the paint. Same squeal when you take an aggressive turn but this is at slow speed. That coupled with the wear on the outside edges makes we really wonder if the alignment is right or if when converting to 4WD the alignment needs to be different.

Thank you for taking your time to help out here.

 

Do you have an alignment spec sheet you could post? Does the truck dog track at all? I don't recall, have you had it aligned since converting to 4wd?

 

@mechanicjon Will post tonight. Not sure about dog tracking. I will have my son drive tonight so i can follow and look.