Belt Squeak when Pressing Brake Pedal

[TheControlVoice]

I was working on my M1008 and I notice that I hear a belt squeak when I press the brake pedal. This happens both while in park and driving.

I am familiar with other belts squeaking but never from a brake pedal. Any ideas on what would be causing this?

 

[nyoffroad]

I was working on my M1008 and I notice that I hear a belt squeak when I press the brake pedal. This happens both while in park and driving.

I am familiar with other belts squeaking but never from a brake pedal. Any ideas on what would be causing this?

Yes, check your power steering drive belt, I bet it's loose or worn down or both.

 

[Keith_J]

Power steering pump provides energy to the power brake booster as well as steering. This is why there are two belts driving the pump, one belt is shared with the driver side alternator. This reduces single failure mode but I've had one broken belt taking out the other. If you lose both power steering pump belts, you have one good pedal assist, stop immediately. That one pedal stroke is from a high pressure accumulator, that gold cylinder on the power brake booster.

Change all three belts every 5 years or 20k miles, whichever comes first.

 

[TheControlVoice]

Power steering pump provides energy to the power brake booster as well as steering. This is why there are two belts driving the pump, one belt is shared with the driver side alternator. This reduces single failure mode but I've had one broken belt taking out the other. If you lose both power steering pump belts, you have one good pedal assist, stop immediately. That one pedal stroke is from a high pressure accumulator, that gold cylinder on the power brake booster.

Change all three belts every 5 years or 20k miles, whichever comes first.

The owner before me converted the truck to 12V. So now it only has the passenger side alternator. Will that affect the braking or steering other than the redundancy of having two belts?

 

[DIVE DIVE]

The owner before me converted the truck to 12V. So now it only has the passenger side alternator. Will that affect the braking or steering other than the redundancy of having two belts?

As long as the one remaining belt is tensioned properly the system should operate normally. Having one belt doesn't affect the capability of the system, only the reliability as Keith J stated. That being said, having two belts does help prevent squeak by providing more surface area for the rotational mechanical energy of the crankshaft to be transferred to the power steering pulley, thereby minimizing any relative motion between the two and preventing any squeaking. If the belt is squeaking it may be time to replace it anyways though.

 

[TheControlVoice]

Ok, I ordered all new belts. I did the bleed procedure from the TM and it looks good so I know its not that. What I did notice is that the tension did look a little lose to me. So I went to tighten it and the adjustment bolt was only hand tight. Once I loosened it all the way I was unable to get the power steering pump to move in any direction and since the previous owner added AC, the compressor is where the driver side alt was.

Is there a special way to adjust the tension? is there more than one bolt holding it in place?

FYI, I ordered the Thexton 383 power steering belt tightener to see if that will help.

 

[ezgn]

Ok, I ordered all new belts. I did the bleed procedure from the TM and it looks good so I know its not that. What I did notice is that the tension did look a little lose to me. So I went to tighten it and the adjustment bolt was only hand tight. Once I loosened it all the way I was unable to get the power steering pump to move in any direction and since the previous owner added AC, the compressor is where the driver side alt was.

Is there a special way to adjust the tension? is there more than one bolt holding it in place?

FYI, I ordered the Thexton 383 power steering belt tightener to see if that will help.

I don't know where you found the Thexton 383 but those are almost non existent. That will definatley help you tighten the belt. If I remember correctly there are two bolts holding the PS pump. Hunt around with a flashlight on the back of the pump and you will find it. Not having those bolts tight is the reason those brackets break.

 

[DIVE DIVE]

 

[TheControlVoice]

I don't know where you found the Thexton 383 but those are almost non existent. That will definatley help you tighten the belt. If I remember correctly there are two bolts holding the PS pump. Hunt around with a flashlight on the back of the pump and you will find it. Not having those bolts tight is the reason those brackets break.

Yeah I was able to find one on eBay for $12. NOS still sealed the package. Got lucky I guess.

 

[TheControlVoice]

View attachment 869597

Thank for the image. Helps a lot. I'll get in there and see if I can get fixed up.

 

[TheControlVoice]

Update. I replaced all of the belts and everything is working like a champ now. The belt for the power steering was slipping so badly that I would basically lose power steering. But all is good now!

 

[nyoffroad]

Update. I replaced all of the belts and everything is working like a champ now. The belt for the power steering was slipping so badly that I would basically lose power steering. But all is good now!

Thanks for the update, many come on and ask questions and we never know if or what fixed the problem.