Oversized Spare Tire & LSP Brake Valve
#1
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Oversized Spare Tire & LSP Brake Valve
I finally got a proper spare tire to match the 32" trail tires on my '87 4Runner. It'll squeeze into the stock spare location under the bed, but it's a tight fit. (Perhaps because there's a receiver hitch eating up a couple inches of the space in there.)
What's bothering me is that the tire is in contact with the load sensing proportioning valve arm thang. I'm sure it's pushing it to the side a bit, but I'm not sure how much.
Since I don't really understand how the LSPV works, I'm not sure if this is a safe situation. I'm headed to Moab shortly (tomorrow!) and I'd rather not drive I-70 through the mountains with brakes that aren't doing what they are supposed to.
Can anyone advise me on whether this is okay? I'm sure I'm not the first one to have this issue.
I'd really rather not give up the cargo space, but if I have to, I'll make it work with the tire on the roof or in the bed. Thanks a ton, in advance.
What's bothering me is that the tire is in contact with the load sensing proportioning valve arm thang. I'm sure it's pushing it to the side a bit, but I'm not sure how much.
Since I don't really understand how the LSPV works, I'm not sure if this is a safe situation. I'm headed to Moab shortly (tomorrow!) and I'd rather not drive I-70 through the mountains with brakes that aren't doing what they are supposed to.
Can anyone advise me on whether this is okay? I'm sure I'm not the first one to have this issue.
I'd really rather not give up the cargo space, but if I have to, I'll make it work with the tire on the roof or in the bed. Thanks a ton, in advance.
#3
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As the arm is Moved up at the axle end, (suspension compressed due to weight in the rear) It opens the valve, allowing the full amount of fluid through, thus increasing rear braking performance.
It is safe to cut the arm, and ziptie/clamp the remaining portion in the UP position. All it will do is increase the rear brake bias (but not to a rear lockup situation)
It is safe to cut the arm, and ziptie/clamp the remaining portion in the UP position. All it will do is increase the rear brake bias (but not to a rear lockup situation)
#4
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I wouldn't worry about it. Since you have larger tires anyway it might be a good idea to make a spacer to lift the rod up giving a little more power to the rear.
On my old 4runner I just cut it and zip tied it up like mentioned above. My current truck came from the factory without an LSPV all together.
On my old 4runner I just cut it and zip tied it up like mentioned above. My current truck came from the factory without an LSPV all together.
#5
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Thanks, guys, especially to niall for the explanation of how the LSPV works. I might try to "reshape" it as arlindsay suggests, but it sounds like it's not a huge issue.
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