Q: What happens if Load Sensing Proportionate Valve is deleted and brakes are connected directly?

asked by on January 26, 2017

When I apply brakes on my Toyota Qualis (Indian Version of Toyota Kijang) at high speeds, it vibrates the rear. Loacal mechanic said it happens because of faulty LSPV and will get cleared if LSPV is deleted and brakes are directly connected using seperate pipes. I am not sure about the handling of my car after this work is done. Kindly please advice me on this issue also about the problems of deleting the LSPV. Expecting an earlier reply. Thanking You Midhun Varma midhunvarma1991@gmail.com Ph No. 0091 9745904901

My car has 312270 miles.
My car has a manual transmission.

If you delete the proportioning valve, too much brake line pressure will be directed to the rear brakes, and too little to the front, thus possibly causing the rear brakes to lock up with loss of control of the vehicle. There is no circumstance under which it is safe, acceptable, or professional to remove essential parts of the braking system that were designed in by Toyota at great engineering effort and expense. Furthermore, the brake vibration has absolutely nothing to do the proportioning valve. The drums are probably out of round and/or have high spots, hard spots, or other defects. If you put new drums on, use Toyota OEM drums only in order to avoid further problems. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

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