On my 98 the abs and brake light r on and the brake peddle feels soft and I have very limited braking is it the master cylinder? I should add I don’t drive this truck very much I let my 60 something year old dad drive it around so I have not driven it much with this issue he also told me that the electric brake controller is not working correctly is it related? the truck has 4 wheel abs.

 

Help............

 

if its a brak problem then i dont know...

if the speed sensor in the rear differential gets bad, and the mph needle in the dash fluctuates, the brake and ABS lights go on too.

had that problem in 3 different 98's already

 

if it were the speed sensor would the brake peddle be soft?

 

Maybe, if its bypassing the anti-lock.

Check the fluid in the resevoir (sp/?).
Check the speed sensor in the top of the rear end and the pigtail that hooks to it.

Does your truck have the arm on the rear end that hooks to a proportioning valve on the frame? (More load=more brakes) I have a 98 3/4 parts truck with that and I am not sure how it works with abs.

 

the fluid was a little low pads are good on the front and no signs of leaks

 

I do not see an arm on the rear end that hooks to a proportioning valve on the frame.

 

The rear end in this truck is out of a 2001 I don’t think it is an issue but I just thought I would throw it out there.