Poor braking

Talked to Peterbilt the this morning as there was going to call me, Engineering went through my whole air brake system and did not find any problems.

But they are going to change the shoes to a more aggressive shoe and put new drums on under warranty. They just have to check with the local rep.

This truck has no protection valves in the system.... They said I did not need to check pressure tho brake cans.

Thanks again for your help I have learned alot about brakes in the last month or so !!!

Best Regards
Carl

 

I am not using pads, But using shoes with brake linings. I would say more of a semi metallic lining and heavier drums.
Kind of weird I bought as a vocational truck and they know that !! this should have been done while they were building the truck.

 

The truck is set up to haul a trailer and as long as I own this truck I will not be hauling any trailers, It has a trolley brake so I am sure there is a protection valve some where if not it will be up to the next owner to deal with it.

I added the set up for a trailer for resale only.

 

Well not having any luck with a solution with my poor braking, Went to N/E kenworth they went through everything checked slack adjuster angles ETC. No problems found. Palmer Spring Co. could not find any problems either.

Palmer Spring put me in touch with a with there retired brake guy and had the best answer of the month, He said these new trucks with ABS systems are using low friction shoes cause they don't want the ABS coming on and are a high mileage shoe. And that is what it feels like there is no friction !!!

He made the most sense our of anyone who has who has been involved with my truck, That being said Monday on I am having all new heavy duty drums and Marathon Heat Shield brakes put on my truck and see how it goes after that.

 

( How do you measure air presser at the drum ??????????? )
I don't know how to measure pressure at the drum but I measured it at the air can.

I guess you can't read very good, Go back and read my posts, I think you will see that I said was applied pressure gauge is a 25 pounds the actual pressure at the can is 23 pounds.

According to Jeff at Marathon Brakes that truck empty should go into anti-lock at 25 pounds of supplied air. I can bring the supplied pressure to the air cans to 45 to 50 pounds of air to the drums and not get into anti-lock.

There does not seem to be any friction when the brakes are applied compared to other truck I have driven.