Our W124 wagon has developed a slight pull and steer to the left under heavy braking. We've noticed that at heavy braking at 5-MPH causes the car and steering wheel to turn left.

We have done the following:

1) swapped left & right tires;
2) swapped with new 205/55ZR16 tires vs. 215/45ZR17 tires;
3) flushed all brake calipers;
4) installed new front pads;
5) installed new front brake hoses;
6) checked rotors for warping.

Pistons in calipers (1994 500SL) freely move and there is no leaking.
Front suspension (bushings (SportLine), ball joints, links, springs (SportLine), struts (Bilstein Sport) ) were all changed out about 1.5-years ago.

Any other ideas?

PS: Since we changed out from 300TE to 400E hubs, do we need to change out the links (tie-rod, draglink, etc.) to those for the 400E or is that only necessary if we change out lower-control arms?

If you have just changed the hubs and had it realigned, you should not have to change the rest of the suspension. It sounds like you've pretty well redesigned the front suspension/brakes. However, hard braking pulls almost always translate into less braking force on one side or the other. You checked the rotors for warp, which should not produce a hard pull anyway. Check you pads for contamination, check the surfaces of the rotors, front and back. You may have a problem with the proportioning valve for the front brakes (possible, but unlikely, if your car even has one). If all else fails, have the brake pedal moved to the right side of the accelerator pedal. The offset should help. :):):) (dumb joke). There is a remote possibility it could be suspension related, but something would have to be really loose. Make sure the calipers are well secured to the steering knockles as well. Good Luck..

You changed the front brake hoses but not the rear. Do the rear brakes have flex hoses?

David

You're On The Right Side
 

Brother of The Benz,ke6dcj
Boy, you've rebuilt from the roof down.
It still rings a bell in my gray matter that your problem is in the right front caliper.
A stuck or sluggish piston.
Beyond that I'm at wits end.
Have you checked the tire pressure, are they equal?
Happy Trails Beep Beep from The Spiderman in Houston!!!

I would sure like to see the alignment measurements. Often with oversize tires the caster is decreased on the left side to overcome the general tendency to go right. This then appears as a small brake pull when the car does as it should with such differences.

Also the toe often changes greatly during braking. If you let that package get toed out during braking everything else will be magnified tremendously.

The front suspension was not designed to handle the forces of such tires (or the weight). You will always be living a compromise.

4 Wheel Independant Suspension
 

Brother of The Benz, be459
All chassis with 4 wheel independant suspension must have a flexible brake fluid hose at each wheel, whereas a solid rear axle has just one flexible brake hose.
After 14 years and 177,000 miles I've replaced the 4 hoses on my 1987 300E.
Happy Trails Beep Beep from The Spiderman in Houston!!!