Four Wheeler Tech Editor Verne Simons’ Response
Shown is a disassemble OEM ( non-adjustable ) brake proportioning valve from a Jeep TJ or XJ. on the right is the front brake inlet line and two front brake wall socket lines. The yellow appliance on the bottomland is a switch that probably turned on a dumbbell light if something in the bracken fluid mechanics goes south, like if one of the brake circuits ( front or rear ) goes dry. On the left the spring and speculator about surely act as a residual press valve to keep some pressure on the raise barrel brakes that these vehicles would have. Dear Ryan, This is an emergence that rears its ugly forefront when swapping brakes around on vehicles ( like swapping from drum brakes to discs ) or when a different axle or axles ( with unlike brakes ) are swapped in place of the factory parts. It ‘s a bit surprising and exciting when you ‘re precisely scantily on the brakes and the rear tires lock up. There are a few ways to make things right, some better than others. First you can try to swap more than just the actual brakes themselves between vehicles, and by that I mean besides swapping the brake victor and factory proportion valve, but that may not work in all cases. It could work if you are upgrading brakes on an older vehicle using factory parts for a former translation of the lapp vehicle. We ‘re thinking of parts-swapping within similar-year Jeep CJs ( magnetic disk brakes up front ), Wranglers ( rear magnetic disk brakes ) or within Suzuki Samurais and Sidekicks/Trackers where many parts interchange, for model.
This is Wilwood PN 260-11179, an adjustable aftermarket proportioning valve. It ‘s used to adjustably lower the come of hydraulic coerce that gets sent to the rear brakes. That makes them lock up belated than they would if the full pressure was sent to them from the passkey cylinder. This proportioning valve besides comes with a press switch that can be used to turn your brake lights on when you pressurize the system ( i.e. push the pedal ). After all, brake systems work because the size of the hydraulic cylinders in the brake maestro cylinder and the front or rear brakes ( be they drum/drum, disc/drum, or disc/disc ) are sized specifically to work in junction with each other. indeed if you good swap brakes around between manufacturers or unlike models, you ‘ll about surely need to add early parts—aftermarket parts. That ‘s because chances are the sizes of the brake cylinders for the disk or drums wo n’t be the lapp as what you removed. As a result the brakes will either work besides well or not equally well. That could mean the front brakes doing all the ferment or the rear brakes locking up at the hint of applying the brakes. fortunately, aftermarket parts can fix this issue.
Adjustable Brake Proportioning Valve
The first part you mention is an adjustable proportion valve, and this can be used to decrease the potency of either the front man or the buttocks brake circuit ( wherever it is plumbed ) to better match what the other end of the brake system is doing. In our font that has about always meant the rise brakes lock up much sooner than the fronts do their job. The opposite is harder to notice ( where the battlefront brakes are doing all the ferment ). What we ‘ve done when the rear brake employment besides well is install an aftermarket adjustable proportioning valve in the buttocks brake tour and then use it to “ turn down ” the potency of those brakes. To do this you need to install the part and do some closed-course testing. ( You can pretend you are a professional driver, and we hold no province for the result of your tests. ) by and large, while driving lento on a gravel road, we want the rear brakes to lock up fair a little act before the fronts. Adjust consequently for your application. There are a few adjustable brake proportioning valves on the market, and they range in price correlate with the choice ( or lack thereof ) with which they are built. We ‘ve used a few from Wilwood and would solidly recommend them or parts from other big-name brake manufacturers. We ‘ve besides used some cheaper adjustable proportioning valves with success, but this is one area of vehicle change that you truly do n’t want to compromise with cheap parts, particularly if you are working on a vehicle that you road repel frequently, tow with, or generally fill with the lives of folks you care about. If it ‘s a beater trail carriage that gets trailered to the chase, “ parts is parts. ” After swapping axles in our 2001 Chevy Blazer and adding large magnetic disk brakes to the rear Ford 9-inch, the buttocks tires would lock up at the hint of applying the brakes. It ‘s great that our brakes were super firm, but besides basically undrivable. We were able to install the Wilwood PN : 260-11179 in the truck to solve this problem and besides bypass the factory ABS, which was n’t working with our fancy new axles anyhow. We ‘ve used Wilwood PN : 260-11179 and Wilwood PN : 260-8419 with success in the past. The first base one even worked closely absolutely to eliminate the factory ABS organization on a 2001 S-10 Blazer that had a pair of Ford F-150 axles under it and disc brakes on the buttocks Ford 9-inch axle.
Residual Pressure Valves: Also Helpful
Another couple of parts that can be helpful, besides from Wilwood, particularly if you are not upgrading your master cylinder and a functional OEM brake proportioning valve or adjustable valve, are minor inline remainder coerce valves. These small parts hold either 2 pounds or 10 pounds of brake press. That remainder imperativeness helps keep the brake parts in position therefore when you hit the brakes, you do n’t have to pump the brakes to push the parts back in place. The 2-pound unit, PN : 260-13783, is used for phonograph record brakes ( to keep the pads near to the rotors ), and the 10-pound unit, PN : 260-13784, is used to keep barrel brake shoes close to the drums.
Xem thêm: The Complete Brake Job
These are reasonably older versions of the Wilwood remainder coerce valves that can be plumbed inline to help keep you from having to pump the brakes on some braking systems when you add drums or disk. “ Techline ” is the monthly doubt and solution column by Four Wheeler technical school editor program Verne Simons, who tries to answer any and all technical questions sent his way by readers. Verne ‘s genius is by and large focused on off-road technical school, but he besides has a background in geology, biota, some have in cook, music trivium, useless facts, and more, so do n’t be shy and he ‘ll give you an answer—right or wrong ! That is, unless it ‘s completely off subject. Verne is available for Techline questions at firstname.lastname@example.org or hit him up on Facebook or @ Verne.Simons on Instagram .