[kyle_blake]

Hi

Just wondering if anyone might have a suggestion on where I might look to help diagnose why I'm feeling braking in my steering wheel when light braking? Like, sticky or something. The car stops well, drives straight.

All the calipers are new and bolts torqued to spec. Wheels nuts are torqued to spec.

Over the last couple years I've done a number of things so I don't know what "one thing" that changed so i can undo but here is some of the work done.

Vehicle : 69 gto, front disc, rear drums.

New Calipers
New Pads ac delco
New Rotors ac delco and good inner outer bearings
New sway bar bushings and end links.
New Lower control arm Moog bushings with new Moog ball joint
QA1 Coil over's in the front.
Lower control arm bolts tightened with vehicle weight.

Still old Upper control arm bushings.
I don't see any worn out parts in tie rods etc or front end rods/parts.

Maybe you can steer me in right directions if you've had something like this before.

Thanks for reading!

[Schurkey]

WHAT DO YOU MEAN "feeling braking in my steering wheel"?

What does the steering wheel DO? Shake? If so, most-likely cause is warped rotor(s), but pull the handle on the park brake, gradually apply the park brake pedal at ~25 mph, and verify that the rear brakes aren't causing the shake. With the handle pulled, the park brake will release as soon as you let-off the pedal, so they're not locked-on.

Upper control arm bushings are suspect based on age. Same for the upper ball joints.

[kyle_blake]

Thanks . No it doesn't shake like that. You can just feel the brakes , assume front, applying ..... in the steering wheel. If that makes sense? Sorry about not finding the right word. The rotor's runout were checked and were within spec.

I think it must of been going from stock spring/shock suspension to new QA1 coil over and only doing half the lower ball joints and bushings. Perhaps it is a slight movement because everything isn't being held in place . Ok thanks.

the e-brake pedal suggestion at 25 , I'll try - thanks everyone.

[Schurkey]

Originally Posted by kyle_blake

No it doesn't shake like that. You can just feel the brakes , assume front, applying ..... in the steering wheel. If that makes sense?

No, it does not make sense.

Describe what the steering wheel does.

Originally Posted by kyle_blake

The rotor's runout were checked and were within spec.

What about thickness variation?

[JLMounce]

While the outward appearance of the upper control arm bushings may "look" okay, you can't tell what is happening inside the bushing. If the rubber has ripped away from the sleeve, there could be a lot of deflection occurring in the upper control arms.

If there is enough deflection in the control arm, this can exhibit as a toe change under braking, accelerating or turning. You can feel toe changes in your steering wheel which act as kind of a pulling sensation.

As you apply the brakes to you have to correct the attitude of the car, or do you feel a sensation as if the vehicle is yawing in one or both directions as brakes are applied?

That would all be my first inclination, but I believe you should also check the rest of the steering system to be sure. Get under the car and press/pull at various parts of the steering. You should have no looseness in the tie rods, drag link, pitman arm or idler arm. Some movement will always occur, but any movement should feel tight and controlled. If there's any clunking or the parts can be easily moved, it's time for replacement. Also check your rag joint.

[kyle_blake]

Schurkey -> Thanks again for you immediate advise on the forum. It's like a sticking sensation, no car pull right or left, the steering wheel does not move right or left during braking, no vibration like if one was experience rotors that are warped - as I know that feeling from when i was a kid. There is no change in the feel as the car brakes, like if there was some sort of "gliding across rotor surface change". It's just sorta grabbing clunky. I've probably failed in my description, lol. The previous stock GM rotors and PADS had a bunch of RV sealant on the back of pads to (i assume) keep them in place or maybe prevent squealing. I do not know.

I did not check thickness variation.

I need to rule out the back brakes like you said.

JL & SCHURKEY> I don't feel car movement sensation as if car is wanting to mildly change direction. You press brakes and you are like that doesn't feel right, it's this area of why is not connecting firm and tight to rotor is my thought. I think you are right I'm going to go under there and do full assessment. It may just come down to all the top end control arm not holding it and as i brake it's moving the bushings that slight amount making it loose when slightly braking. rag joint is good idea to check as well as all the parallelogram front end design. ok thanks guys i have my marching orders. as always thank you everyone

[steve25]

If you narrow it down to the front then jack the front up on each side and have someone spin the tire while you apply the brakes lightly.

If you do not feel anything then you know the issue is due to suspension loading during brake applications.

[Lemans64]

Another thing to watch for is the outer pad moving, can cause clunk. Old pads had (Silicone) for lack of better terms on outside pads, this can help pads from moving.
Outside pads had tabs on top and bottom of the metal part, these need to be bend over to make them stay tight on the caliper. Either take pad out
and squeeze tabs down or tap down with hammer or have somebody put foot on brake pedal with Chisel between bottom of pad and rotor center section
and then bend tabs down on top of pad to make pads secure to caliper.

[Holeshot71]

I would definitely recheck everything, make sure nothing is loose or maybe a tire rubbing.

[kyle_blake]

Hi,

I spent some time today on this. jacked front end up.

Friend turned the wheel while i hit brake pedal (car off) . really couldn't say that was an effective test. Both wheels stopped obviously, even the slightest pedal wasn't any noticeable wobble and buddy would of had to try pretty hard to continue turning tire.

There is a slight slight drag on each of these when free wheeling the tire but nothing that stands out as horrible or wrong. No scores on rotors.

My next test was the 12 o 'clock 6 o'clock tire test. Passenger side - that yielded some clicking. then 9 and 3 test - tight no movement. Ah hah I thought? So I went under with a light, and rocked wheel up/down with 1 arm and could see the rotor slightly moving.

I tightened to seat it , slight drag. then castlenut on , had to back off to next cotter pin hole alignment and insert it. always told back off!

All I can think is maybe a slight tighten more to next cotter pin hole. or use a different castlenut where maybe it lines up right at the tight preload.

The drivers side has the slightest movement up/down and no movement right/left.

Thoughts? Thanks in advance. tgif!

[steve25]

It could be that.
How are the spindles were the ID of each bearing seat.

If you slide a bearing on by itself how does it feel?


Even with new bearings with the nut set tight there could be movement in there.

Remember your dealing with something that’s round and because of that .001” of play turns into over .003” of wahble .

[kyle_blake]

Thanks Steve.

I remember taking the first sets of bearings back to the parts store as it would not fit on. We switched brands , he measured the ID and verified it should be what it was. It fit on the spindle when i tested it dry. It fit snug and it fit good. I repacked them and used them. From a relatively new to the job guy I feel they are the right bearings.

I saw a video online that basically turned the rotor by hand and torqued nut down to 200 inch pounds. I guess that seats the bearing. Then he backed off the nut and torqued to 20 inch pounds. Called it a day.

My questions is, and it's obvious I'm sure, clearly there should not be any movement up/down side-to-side with tire on? If that is the case then yah bearing or perhaps spindle is slightly damaged or worn down in a section causing it to be off is t he current path of thought.

Thanks again PY. I will pry the tires up and down off the ground to see for slop in the upper balljoint but I don't believe there is any last time I tried and that would be a different problem.

[steve25]

I would also look very carefully to confirm that the bearing races are seated straight.

[kyle_blake]

right out of manual.

only thing i didn't do is raise the lower control arm a bit like it suggests and i did it without the tire on.

i'll keep looking.

[kyle_blake]

Hi,
- Rag Joint - OK
- No loose front end parts. I did dry steer on pavement with friend turning wheel
- Jacked up each lower control arm and tested upper ball joint , no movement.
- Bearings - Checked and ended up seating them harder but ultimately returned nut to same position as before. Checked with a mechanic on this and he said going to the next pin location "up" would in theory take up the movement I may feel with my "up & down wheel on test" BUT at the expense of having to replace the bearing sooner than normal BUT if that is what it takes to not have CLEARANCE then that is what it takes.
I found that the outboard pad on the drivers side was not secured using the hammer on the tabs. Passenger was - so I did that and test drove it. Crossing fingers.
Very "creaky" in pedal pushing (like a 1950’s relic) and in steering wheel the “vibration”. I Even felt a chatter pad slap coming to a light ( passenger I think ) so turned around and came home.
Jacked up again.
- Run out on passenger side 0.003
- Run out on drivers side 0.002


Rotors: The Ac Delco Silver 18A07A (The bearing races are already installed from factory)
-----Phoned Acdelco to find run out spec, she couldn’t find the rotor in her inventory at all.
Wagner Brake ThermoQuiet QC52 Ceramic Disc Pad Set
----- Phoned Wagner and they said there should be no need to hammer those tabs down and has offered to exchange pads with me and I'll send back those ones.

Drivers side -> spun the rotor around by hand and you can hear the pad hit every revolution.
Passenger side -> is a complete 100% drag pad noise all the time not a "touch on/touch off" like drivers. Harder to rotate by hand

I can only think of trying the following:
1- Try next notch up on castle nut on each side, try up/down tire test to feel if slight creek movement, Then drive, torque wheels nuts to 80 ft/pounds
2- Try RV Compound on back of inner pad and on piston , Then Drive
If that doesn’t work, well try the replacement pads next week.
Or I suppose take to a shop and perhaps their parts source can get me the right matching parts, something is a miss.

Sorry I don’t have a micrometer or caliper to check thickness variations.
Appreciate any comments, have a nice weekend.

[Sirrotica]

Just a suggestion, I would get a heat gun and drive the car around where you're braking consistently. After 10 minutes or so take a reading on each front wheel and see if they're close to the same heat readings. Could be a sticking caliper piston,or caliper slides, or pins.

Bad flex hoses can also cause the fluid to get trapped in the calipers, and unable to return. it will keep pressure on one caliper causing it to drag.

Rusted crimp connections on the flex hoses, or delamination of the rubber will cause a one way valve that can trap residual pressure. The latest I've heard is that flex hose manufacturers wanr them replaced same as tires, 6-8 years is their projected life according to manufacturers.

With a caliper dragging, it will start to go out of round when it's heated due to friction.

.002-.003 runout is fine on most any car/truck, you're not going to detect any pulsation with that little runout.

When adjusting the wheel bearings, better to be on the loose side than too tight. As the bearing gets warmer it will take up clearance. If there's not enough clearance to begin with, it will either seize, or score the bearings and races, I've seen it many times when someone tries to adjust a wheel bearing too tight, they're not going to go the normal distance.

BTW, I've ever had any brake/handling abnormalities due to wheel bearing adjustments in over 50 years of wrenching. Most times either the bearings are quiet, or their noisy due to insufficient grease, and galling, that's about the extent of problems with wheel bearings on RWD vehicles.

One other thing I have run into when the car is feeling weird under braking, A few times I've seen rear control arm bushings deteriorated to the point of causing rear steer. Unlikely, but possible you're looking at the wrong end of the car, it never hurts to rule out rear bushings.

[Schurkey]

Originally Posted by kyle_blake

- Bearings - Checked and ended up seating them harder but ultimately returned nut to same position as before. Checked with a mechanic on this and he said going to the next pin location "up" would in theory take up the movement I may feel with my "up & down wheel on test" BUT at the expense of having to replace the bearing sooner than normal BUT if that is what it takes to not have CLEARANCE then that is what it takes.

This is CRAZY.

You do not have ball bearings. Ball wheel bearings need preload. Your vehicle uses tapered-roller bearings. Tapered-roller wheel bearings are installed with slight clearance, (free play) EXACTLY AS EXPLAINED IN THE TWO-PICTURE GUIDE you posted as a thumbnail image previously.

Tapered-roller wheel bearings installed with preload will fail prematurely.

There are probably two cotter pin holes in the spindle, at 90-degrees to each other. Use the one that minimizes free-play.

Originally Posted by kyle_blake

- Run out on passenger side 0.003
- Run out on drivers side 0.002

Remember, when checking runout, the bearings need to have just enough preload to prevent free-play. But they must have slight free-play when in actual use.

0.003 seems like a lot, IF it's being measured properly. I don't remember what the spec is, though. I put 12.5" rotors on my K2500, these rotors are "riveted" to the sealed-bearing hubs via the lug-studs. Runout was .001.

Originally Posted by kyle_blake

Phoned Wagner and they said there should be no need to hammer those tabs down and has offered to exchange pads with me and I'll send back those ones.

I've had to hammer-fit the outboard pad on every similar pad set I've installed since 1980. Your "phone tech" person is wrong.

Originally Posted by kyle_blake

Drivers side -> spun the rotor around by hand and you can hear the pad hit every revolution.
Passenger side -> is a complete 100% drag pad noise all the time not a "touch on/touch off" like drivers. Harder to rotate by hand

MAYBE worth looking into the calipers, to see if they've got some minor sticking--either the piston in the bore, or the caliper on the guide pins/sleeves.

Originally Posted by kyle_blake

I can only think of trying the following:
1- Try next notch up on castle nut on each side, try up/down tire test to feel if slight creek movement, Then drive, torque wheels nuts to 80 ft/pounds

Adjust the wheel bearings exactly as shown in the previous post--when you're done, the bearings WILL have some slight free-play.

Originally Posted by kyle_blake

2- Try RV Compound on back of inner pad and on piston

I have no idea what "RV Compound" is. If the pads are installed properly, I can pretty-much guarantee you don't need "Compound" of any sort.

[PontiacHO]

If something in the suspension is loose, (even the rear control arm bushings) you’re going to feel the car change it’s “tracking” when the brakes are applied initially. Checking the runout on the rotors is first, followed by loose play in the wheels-bearings, then some observing physical movement in the front and rear suspension bushings with a big pry bar…

[kyle_blake]

Hi,

Ok - thanks for teaching me!

The preload is clearly and 100% not the issue. Even when I went back for second time I still resorted to backing it off to the same adjustment it was. As seen in the picture I posted. The small movement up/down that I detected with tire raised - has to be acceptable. My mistake.

When I first removed my original pads from this car it had genuine GM rotors and pads and on the back side was thermal paste or RTV or whatever orange stuff. Sorry I meant " RTV " sealant was used on backside of pads I took off not RV.

MAYBE worth looking into the calipers, to see if they've got some minor sticking--either the piston in the bore, or the caliper on the guide pins/sleeves.

----> Brand new calipers on both sides, brand new rubber hoses, brand new guide pins.

The only thing re-used was the inboard clip that fits in the piston. I mean this is where RTV sealant and the pin would rule out any "movement" off piston during application/retraction.

---> I will look into it this.

If the passenger caliper is sticking, then that heat test is a great idea! I do see some spots now on the passenger rotor which shouldn't be there. Maybe heat spots or pad material - I'll bring my tester and go for drive after pulling both sides apart one more time.

Using Sil-Glyde Silicone Brake Lubricant on the pins FYI

Curious, there is no way of testing the sticking caliper in the garage , right ? I can't like take pad out and press brake and have piston come out and then compress back in with c-clamp w/ old pad to kinda "work it"?

I do find 0.003 and 0.002 quite low and should be acceptable? But I mean it's only been 230 km I was stuck driving like this with this issue. Makes me think the pad/rotor material is just not compatible. Maybe semi-metallic pads should of been used.

I'll report back TY.

FYI, rear end has new qa1 shocks, new edelbock lower control arms. only thing not touched is the upper control arms but thank you for your help, it is something to consider. I will jack up rear dif and put a pry bar under the rear tires and see if there is any up/down - right left movement. if that is what you mean?

[george kujanski]

Back in the day, pads came with the 'goop" to put on the back side of the pads To dampen vibration (prevent squeal). Nowadays all the pads i get have a damping pad installed on the back side. Haven't seen the goop used in years.

George