[rustout 89]

The brake warning light on my 89 4x4 will not go out. I replaced the front pads which were down pretty far thinking that the extra travel was cauining a low pressure situation. The light glows stronger when the parking brake is on but it stays lit even when releasing the parking brake. Could I have gotten air in the system form letting the pads run so low??? also when I was doing the brake work I noticed that the boot on the axle shaft is torn. Do the split boot kits work?? what should I use to clean the joint before repacking??

 

[Tha_Boom]

Do you have abs? if so it might be an issue with it.

as for split boots i havent seen them last real long. for cleaning them use some break cleaner and load them up with some grease.

 

[rustout 89]

thanks for the help. But no ABS on my 130K trusty old rust bucket. Just front disc, rear drum, loose parking brake, standard system. Maybe I should try bleeding them, although I have not disconnected any hydraulics.

 

[Beaker28]

89 4x4 with same problem

I have an '89 S-15 4x4 that had the same problem. The light stayed on no matter what, and engaging the parking brake made it brighter. I'm pretty sure that your truck also has an older form of abs for the rear brakes. If you look under the hood, there should be a small black box right beside your master cylinder. That is the brake computer/controller. I replaced mine and the light went off! It hasn't come back on since.
I purchased the replacement controller from a wrecking yard for about ten bucks. I have no idea how this system works, but I know the rear wheels never lock up even when I attempt to do so. There is a slight vibration in the pedal that indicates when the abs is working. Hope this works for you too!
"Rusty but trusty" 384000km on original tranny!

 

[rustout 89]

thanks for the tip I will look for the box. But on another topic. My tranny works fine at 130K It has never had a fluid change. Most shops advize against doing one at this late date. With all those miles on yours what is your opinion???

 

[88_S10]

Any word on this? My 90 S10 Tahoe 2wd 4.3 w / no abs has the same exact problem....

The brake warning light on my 89 4x4 will not go out. I replaced the front pads which were down pretty far thinking that the extra travel was cauining a low pressure situation. The light glows stronger when the parking brake is on but it stays lit even when releasing the parking brake. Could I have gotten air in the system form letting the pads run so low??? also when I was doing the brake work I noticed that the boot on the axle shaft is torn. Do the split boot kits work?? what should I use to clean the joint before repacking??

 

[pare_john]

it is possable that your E-brake switch is sticking partially. also the light will come on where you are low on fluid

 

[Rhotpursuit]

I had this exact same problem on my Z71...brake light on dash stayed on...got a little brighter when e-brake engaged...It was the brake light switch....not the e-brake switch.

 

[88_S10]

You are correct - I used my code scanner and found out it was the brake light switch. When the brake pedal is not being pushed, the switch should be in all the way. Mine, however, was still out a tiny bit, just not enough to make the brake light go on. So, I followed the manual and adjusted it, works great now.

I had this exact same problem on my Z71...brake light on dash stayed on...got a little brighter when e-brake engaged...It was the brake light switch....not the e-brake switch.

 

[cavymeister]

thanks for the tip I will look for the box. But on another topic. My tranny works fine at 130K It has never had a fluid change. Most shops advize against doing one at this late date. With all those miles on yours what is your opinion???

Leave it as is. That's a lot of miles for no oil change. If you put new fluid in, you'll probably break loose some of the crud that has build up and it's likeley to block passages. This is one of those cases of if it ain't borked, don't fix it.