phoenix_iii

*edit* Pretty sure it's a brake related issue. See
https://mbworld.org/forums/c-class-w...s-welcome.html

Bought the car in need of an alignment.

Two rims were bent!

4 new wheels and tires, and alignment (amongst other work performed, inspection, all fluids, etc)

Car still pulls to the right. I called the shop to make sure that the alignment was done (The work order was pretty large, maybe it didn't get done). It was done, and it spec'd out correctly according to the person I spoke with (who I believe to be the owner, older German fellow, handlebar with curled ends mustache, etc). This is a german car specialty place, looks like predominantly 80s and 90s, with a few newer (2000+).

Anyway, with everything in spec, and it still pulling to the right, my questions are...

1) Is there any difference in tire life in 'leaving it' as it and holding the wheel, vs. what I've read (through searching) and adjusting the right side camber/caster (I forget which)? Wouldn't the latter actually wear the tires out faster? I'd rather be able to let go of the wheel and have it track straight if the tire life is the same.

2) What should I do? Bring it to an MB dealer, Pay to have them check the alignment, and then? If it checks out, it's back to which is better, driving as is or adjusting it (and possibly more tire wear?). Obviously if they check it and it's not right, then I have something to get back from the Indy shop.

Thoughts? I am going to drive the car more today, hopefully find a parking lot (level) I can use. It's severe enough it's not the gradient of the road, I am pretty sure of that already...


*Edit* Checked Tire pressure (wheels and tires Hunter Road Force Balanced from tirerack.com), right side already up by 1lb (35 and 36 respectively).

My other thought was possibly a sticking caliper. I have a laser thermometer I will use at the end of my next trip (later tonight, about 15 miles).

johnand

Ask the shop where you had the alignment done for a printout. Then post it here, and we can see if that is you problem. You could also have a radial pull from the tires. Swap the front tires from side to side and see if it still pulls.

Also these cars need to be setup to have 1 degree more positive caster on the passenger side to minimize pull from the crown.

phoenix_iii

I think I've got a brake problem. I will search, but it may need a new thread, I've never experienced this in my many car history, but in theory, it makes sense.

First, I have a temperature discrepancy (in Fahrenheit, so not very much, but enough). Front Right is about 8degrees warmer than front left (measuring at the same spot on the caliper), and rear left is about 2.5 degrees warmer than rear right. This would be one 'circuit', to my understanding, the front right and rear right are on one circuit, and the complementary wheels on the other.

What's interesting, is, at times, if in 'drive', and going from a stop to just barely in motion, if I keep jabbing the brakes, I can get the wheel to go to the one o'clock position (very visably off/out of alignment). To me, this would show that the front right (And rear left it seems) are grabbing a head of, or are just barely rubbing, causing the drift.

Pads look NEW around the car, tons of meat, so maybe recently changed and later on it would show a discrepency in use.

Thoughts?

skittles

just want to give a possibility coz something similar happend to me. i did all i could to fix the alignment. had the alignment done at the dealer, replaced bushing, tires, sway bar bushings. and i still had a pull to the right also. ended up being a leaking right strut. weird. i repalced both front struts and was ok after. but try the checking your brakes also. the problem might be just there.

phoenix_iii

Thank you for posting that. I think I do have a brake problem. New thread here.
https://mbworld.org/forums/c-class-w...s-welcome.html

mleskovar

Red flag.....what bent the rims? Was more damage done? As far as pulling goes...I don't see how you can live with it, especially on long trips.

phoenix_iii

Was a city car. Some nasty potholes when I went to go visit. One tire had a big bubble in it to boot.

The front bumper has a decent ding on it (spydered the paint), but ALL body panels line up, and the shop was responsible for the fairly rigorous PA inspection, and trying to get me for anything else... =)

Clean Carfax, and was a 2005 CPO Car (how the Previous Owner got it).

If you are familiar with brakes please visit
https://mbworld.org/forums/c-class-w...s-welcome.html

Glyn M Ruck

+1 the 1 deg more castor passenger side is crucial.

phoenix_iii

Thank you Glyn, your input is always welcome.

*edit* Pretty sure it's a brake related issue. See
https://mbworld.org/forums/c-class-w...s-welcome.html

mleskovar

Can't access link anymore. Does it pull when brakes are both cold and hot? Have you tried jacking it up and turning the wheels by hand to see if you feel any added resistance?

phoenix_iii

Fixed all links.

https://mbworld.org/forums/c-class-w...s-welcome.html


Pulls/repeatable hot and cold. Have not tried by hand, will do that and swap front two tires (making them go the 'wrong' way) Saturday. Temps range from 140 to 155, so a 7 to 8 degree difference is 'something'

I talked to the tech on the phone again. He doesn't think the temp difference is significant at all, and says it's normal for the brakes not to fully release for the first few feet, and I'm just teasing it. I've never been able to make a steering wheel turn to 1 o'clock, or 1:30, just by touching the brakes on and off...

mleskovar

When you try it, manhandle the tires in all axis to see if anything is loose.

I've seen a loose tie rod end do this, usually accompanied by abnormal tire wear.

phoenix_iii

This makes sense... two bent rims... if she hit something at speed (previous owner)... No one likes my other thread. Here's the meat and potatoes part of it...

"Car originally pulled to the right when I got it. It had two bent wheels, and one of the tires had a bubble. All replaced and should be fine, so I thought.

Car still pulls to the right. Alignment spec'd out correctly according to the MB Indy shop I went to.

Pulled out the laser thermometer after 10 miles trip. I have a temperature discrepancy (in Fahrenheit, so not very much, but enough). Front Right is about 8degrees warmer than front left (measuring at the same spot on the caliper), and rear left is about 2.5 degrees warmer than rear right. This would be one 'circuit', to my understanding, the front right and rear left are on one circuit, and the complementary wheels on the other.

What's interesting, is, at times, if in 'drive', and going from completed stop to just barely in motion, if I keep easing off of the brakes, then brake on, I can get the steering wheel to go to the one o'clock position (very visably off/out of alignment), after having been perfectly in the middle (noon). Sometimes it will just 'shake' or tremor in place [briefly, just in the time from barely rolling to 'full stop'], but I have had it MOVE from noon to 1 o'clock by doing this stop/go slow shaking in place braking several times in a row (3 to 5). To me, this would show that the front right (And rear left it seems) are grabbing ahead of, or are just barely rubbing, causing the drift.

Pads look NEW around the car, tons of meat, so maybe recently changed and later on it would show a discrepancy in use. I am also sure the Indy shop would have liked to have gotten me for new pads.

Tires and wheels were mounted and balanced by the tirerack using excellent equipment, so I mean, I 'could' try swapping wheels around (they are all the oem standard size, unidirectional though).

I've never had this happen before on any car... Is there something else I should be looking at? Should I bring the car to the indy place and have them clean and lube the calipers? They use slide pins, right? Would some one knowledgable recommend any tests I should perform, or need to see a video of the steering wheel 'moving' by the stopped/ 'barely braking' technique?"

FormulaZR

I may be over simplifying this...but is there a chance that the roads you drive on crowned, or do they have a super? I am not saying you don't have a problem with the car, but a road with a cross slope will make the car pull to the downhill side. If, however, this is not the case, then just ignore my suggestion!

phoenix_iii

FZR, it's always a thought, but it's pretty well pulling at this point. Large corporate parking lot to boot. I took the car to work today to try some more tests in the parking lot at 8pm (when I leave work) to verify. I've never seen a car I can make the steering wheel shake (left right) by barely applying/letting off the brake, and make the wheel TURN to the 1:30 position from dead noon... =(

FormulaZR

Yep, you're right. I agree that the braking issue wouldn't be related to a road surface like that. I just wanted to make sure that two individual issues weren't being linked unjustly. However...if it still pulls in a flat parking lot, then my suggestion is clearly not applicable.

Last time I had a brake issue similar to yours it was solved with a brake bleed...but again, probably not your situation!

Best of luck to you!

mleskovar

Also....do you know if the thrust bushings were ever replaced? If one/both were drained it might only show up under braking load.

phoenix_iii

I had it on the list of things to check (amongst the more common tranny plug and CPS). It also does it when not under load, for sure. Took another car this morning, that tracks straight, world of difference.

mleskovar

My car drifted right ever so slightly when it was new so I'm familiar with the problem. Braking didn't affect the drift. Under warranty they replaced the camber bolts, realigned, and it was like a new car. It tracked absolutely dead on and felt like it was on rails going around bends and corners. Your movement of the steering wheel when braking sounds like something is loose and may or may not be associated with the drifting. Stay with it, it's worth the effort to get it right.

phoenix_iii

I appreciate the support. I was actually having nightmares last night about the whole thing... I think she'll be a great car once squared away! I just hope this indy shop doesn't try to take me for a ride.

mleskovar

'01 and '02 C class may have the worst reliability records of any MB ever built. I fixed all but one of my problems (right defrost stepper motor, too hard to access) as they came up and none have reoccurred. The car is rock solid now and despite having 162K miles it feels like new and is a joy to drive.

Glyn M Ruck

You might have one brake caliper over returning. I've explained this elsewhere & will find the thread for you. I recommend you pressure bleed the brakes - see if this makes any difference & then get the car on an alignment machine. Get them to bounce the car on the alignment machine & see if you get any variation in readings. You either have a brake problem or something is loose. I presume that no one has done a hack job on this car and that it has the same brake pads all round & similar rotor condition??? Sorry for late post - saw your PM but the internet went sick with the demise of Michael Jackson.

Glyn M Ruck

Caliper over return

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

I posted this to LILBENZ's thread - copied here. Manual pumping instead of pressure bleeding can sometimes resolve.

Caliper over-return is caused by pushing back the pistons in the caliper further than necessary when changing pads. The pistons have a D shaped cross section seal. When braking the seal sticks to the wall of the bore of the caliper & distorts to allow the piston to move forward against the pad. All that returns the piston with brakes off is the seal going back to it's normal shape. If the pistons are pushed back too far into the caliper when changing pads - i.e. by more than the thickness of the new pads - the seal sticks to the bore - distorts more than normally required - and thus returns further than it should. This gives you a low pedal because you have to displace more brake fluid to bring the pad in contact with the disc. The only fix is to strip & dry the entire braking system. Assemble the calipers, pads & all dry. Use compressed air to blow the pistons, seals & pads hard up against the disc & then bleed the brakes. I have done it many times in racing & it's a right royal PITA. It's frequently the cause of a slighly low or spongy pedal on Mercs & other cars. People frequently go changing flexible pipes etc to try & cure it. Frequently they are partially fixing a symptom without understanding the real, underlying problem.

phoenix_iii

I have a Motive Bleeder, but I had them replace all fluids in the car, and this includes brake fluid... =\ I'm curious about the 'over-returning', haven't heard of that before. The backs of the pads look the same, how about that? . I will see what they say, hopefully the guy will be in tomorrow afternoon and I can talk with him, but he doesn't take me very seriously... =\ Not sure why.

phoenix_iii

Brakes feel good... very good. So it's not low or spongy. Good info to know though!