1998 F150 4X4 - ABS question

It sounds like your rear brakes are taking more of the load than the fronts. Just a guess, mind you ...

The fronts are supposed to take (pulling numbers from the warm dark recesses of the back of my pants to illustrate the point without any attempt to be accurate enough to land an intergallatic space craft anywhere near Mars) 60% of the stopping load, and the rears then take the remaining 40%. Let's assume for a moment that you need brake service, or just had brake service that upset the perverbial apple cart, and now the front brakes are taking

Under such a scenario, AND having no appreciable weight in the back of your truck, it is reasonable tha tthe rear brakes would lock one or the other rear tire depending on other external factors already having been discussed. Perhaps there is air or moisture in the front brakes, or the rear brakes are adjusted a bit too tight, or the front brakes are becoming worn down or they are new but are not the same as the original brakes and thus causing an imbalance in the braking performance.

If there is air or moisture in the lines, the solution is to flush the brake fluid. There are those that suggest this is routine service that ought ot be done every two years, if you have not had this service done then that is where I think I would start. Of all of the things I've listed, flushing the system is the only job that I would not do myself, mostly because it is kind of a pain in the ass to do and I've reached the stage in my life where I have limited tolerance to crawl around under the car yelling at somebody to push the brake pedal and hold it at the bottom until I can get the screw tight again. It is not a difficult job to do, it's just a PITA. It's worth it to me to pay for this service, I do the rest of the stuff myself.

In any case, your ABS is not failing you. Well, it could be failing you, but you have not described the symptoms yet ;-)

Thanks, I think you may be right. Today I started out in reverse for about 40 ft. and pumped the brake hard a few times. After doing this, it seemed to stop most of the lockup. Lockup only seemed to be on the right rear now so my vote is the e-brake cable. I'll know for sure next Sat.

Del.

Mike H wrote:

Thanks Jeff. I am leaning to what Mike H said about the e-brake cable being corroded and hanging up. When I pump my brakes in reverse and then go forward most of the lockup goes away and when it does happen, it seems to be mainly right rear lockup. Thanks for all the help, I really appreciate all the response to my question and I'm glad it's not the ABS system. I'll let you know what I find out on Sat.

Del.

Jeff Strickland wrote:

That would certainly account for the transient nature of your problem.

You just exercised the automatic adjustment mechanism.

While you are looking the parking brake cable and associated parts, you should also take the tires off and look at the rear brakes and the adjusters.

Between the parking brake binding and the adjusters hanging up, we have come full circle to my original guess that you had a brake adjustment issue. We've narrowed the adjustment issues to two areas. There could be more, but these are at the top of the list.

The automatic adjustment is managed by a star wheel inside of the drum brakes. This wheel is at the bottom, and is situated between the two shoes. As the brakes are activated while going in Reverse, the shoes will be moved a small amount opposite of the direction they would move if going forward. This reverse action moves a lever that cranks the star wheel, which spreads the shoes and adjusts them tighter than they were before. You can have a sticky adjuster that prevents one brake from adjusting, or you could simply have no problem and just need to go in Reverse a few times and mash the brakes.

Since you will have the tires off and performing a visual inspection, you can adjust the brakes manually, and this is problably better anyhow ...

Thanks Jeff, good to know I did something right. It's all going to be looked at Saturday, wheels off etc.

Del.

Jeff Strickland wrote:

This is what the dealer found:

- Right side wheel cylinder leaking - contaminated shoes.

- Left side badly out of adjustment. (had very hard time to remove drum)

What I had them do:

- Reline rear brakes.

- Replace both wheel cylinders. (no sense just doing one)

Total bill with tax was $473.46.

It all works now, all is good. Thanks for all the responses and advice, you were all very helpful.

Del.

On Sun, 14 Oct 2007 20:19:26 +0000, Del rearranged some electrons to say:

Remember what I asked on Oct. 6th?

As far as I knew they were or should have been. I had just had the brakes done in july by someone who is very reputable, new shoes, turned drums etc. This obviously happened since or was missed. I do plan on having a talk with them. Thanks for the input, it was all appreciated and yes you nailed it. Thanks again.

Del.

david wrote:

You should say nothing, and move on to a different shop.

You got hosed, and they will never admit that they screwed you, much less make good. Suffer the loss and move on.

Not only was it missed, it was not even looked at.