Ol' Snort
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Mountain Pass
Joined: Dec 2020
Posts: 148
Likes: 143
Stock size master.
The pedal is pretty firm but the rear brakes do not bite hard enough to hold solid. When it was on jack stands, I had someone hold the pedal and I could not turn the wheels with a prybar in the lug nuts. I thought that was good enough but when it was at the muffler shop, only the fronts would hold. We tried an experiment with the fronts on the ground and the rears on the truck. He pulled forward and the rear wheels rolled on the truck deck with me holding full pressure.
I'm wondering if the master cylinder could be bypassing pressure on the rear side and not holding. The only time I have had a master cylinder go bad it had a leak. I'm just wondering if the leak is internal. We have all dealt with new parts that failed right out of the box. That could be the issue.
I haven't driven this truck in so long I forgot what "normal foot pressure" feels like. There is also no vacuum at the booster since I have not started it yet. I didn't want to lite this candle yet without exhaust. If there is a knock in the engine, I want to hear it. Shows you my level of confidence. I crammed two-years of work into six. Don't want to screw it up now.
The pedal is pretty firm but the rear brakes do not bite hard enough to hold solid. When it was on jack stands, I had someone hold the pedal and I could not turn the wheels with a prybar in the lug nuts. I thought that was good enough but when it was at the muffler shop, only the fronts would hold. We tried an experiment with the fronts on the ground and the rears on the truck. He pulled forward and the rear wheels rolled on the truck deck with me holding full pressure.
I'm wondering if the master cylinder could be bypassing pressure on the rear side and not holding. The only time I have had a master cylinder go bad it had a leak. I'm just wondering if the leak is internal. We have all dealt with new parts that failed right out of the box. That could be the issue.
I haven't driven this truck in so long I forgot what "normal foot pressure" feels like. There is also no vacuum at the booster since I have not started it yet. I didn't want to lite this candle yet without exhaust. If there is a knock in the engine, I want to hear it. Shows you my level of confidence. I crammed two-years of work into six. Don't want to screw it up now.
Tuned
Joined: Jul 2021
Posts: 299
Likes: 224
It sounds like the master cylinder to me also. When mine went, I didn’t have any leaks so it would’ve been the seals inside letting fluid blow past and not giving me any brake pressure but since you haven’t started the truck and you don’t have the booster helping out, it would be hard to rule out the booster.
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