2008 yukon build.....Err uh mod thread
#94
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From: Virginia Beach,VA
Been losing air in my rear tires pretty bad, especially since it has gotten colder...usually 3-4 psi overnight.... Got tired of it so i figured out what was going on....
Right rear valve stem (tpms stem anyway) leaking worst of all, had roughly the same response fron the keft rear and left fromt as well...
New stem and some dirt/corrosion removed from around hole in the wheel and a little bit of bead sealer on the inner side of the hole and no more leaks.....
This was the base of the left rear stem, in case anyone is wondering.... Corrosion doesnt hold air.....
Still need to tackle the left front, but its not leaking as bad... Will probably take care of it tomorrow evening.... Sad part in all of this is that the dealer replaced a sensor before i bought the truck and ended up putting 3 tires on it, someone should have noticed this....
Right rear valve stem (tpms stem anyway) leaking worst of all, had roughly the same response fron the keft rear and left fromt as well...
New stem and some dirt/corrosion removed from around hole in the wheel and a little bit of bead sealer on the inner side of the hole and no more leaks.....
This was the base of the left rear stem, in case anyone is wondering.... Corrosion doesnt hold air.....
Still need to tackle the left front, but its not leaking as bad... Will probably take care of it tomorrow evening.... Sad part in all of this is that the dealer replaced a sensor before i bought the truck and ended up putting 3 tires on it, someone should have noticed this....
#95
I measured it!!!
Cam Part number #3207 = 12593207 or 12625436
Covers LC9 LMG LY5
Lift .486/.487 duration @.050 .196/.198 on a 114 LSA
And that cam cleaned up just fine.
Cam Part number #3207 = 12593207 or 12625436
Covers LC9 LMG LY5
Lift .486/.487 duration @.050 .196/.198 on a 114 LSA
And that cam cleaned up just fine.
Last edited by 1FastBrick; 01-26-2016 at 11:46 AM. Reason: 4 digit code on cam.
#97
#99
There should be no difference. deactivation is controlled by the lifters from what I read.
LH6 deactivates the same 4 cylinder's 1,4,6,7
The DOD-specific hardware includes two-stage switching lifters, a lifter oil manifold assembly (located in the valley of the engine), a redesigned lube circuit and oil pump, electronic throttle-by-wire operation, a pressure-activated muffler valve, and an improved E40 engine controller running DOD-specific software.
"In order to eliminate the pumping losses," says Meagher, "you need to disable both the intake and exhaust valve." This results in a completely sealed, deactivated cylinder, which is essentially an air spring being acted upon by a piston. Virtually all the work put into it during compression is returned to the crank during decompression, finally giving credence to the old joke about piston-return springs.
"We disable the valves through a device called a switching lifter," explains Meagher. "This differs from a normal lifter in that there is an inner body and an outer body connected by a spring-loaded pin. For V-8 operation, the pin is fully expanded by the spring so the two pieces act as one and the lifter acts like a regular lifter. When we want to disable the valve operation, we deliver high-pressure oil to a groove in the lifter that leads to the outside end of the pin, forcing the pin to collapse the spring. Now the two parts of the lifter are free to move relative to one another and as the cam lobe pushes on the follower the inner portion of the lifter pushes against another spring at the top of the lifter and does not transfer force to the push rod."
Info above copied from this article--->GM displacement on demand technology
LH6 deactivates the same 4 cylinder's 1,4,6,7
The DOD-specific hardware includes two-stage switching lifters, a lifter oil manifold assembly (located in the valley of the engine), a redesigned lube circuit and oil pump, electronic throttle-by-wire operation, a pressure-activated muffler valve, and an improved E40 engine controller running DOD-specific software.
"In order to eliminate the pumping losses," says Meagher, "you need to disable both the intake and exhaust valve." This results in a completely sealed, deactivated cylinder, which is essentially an air spring being acted upon by a piston. Virtually all the work put into it during compression is returned to the crank during decompression, finally giving credence to the old joke about piston-return springs.
"We disable the valves through a device called a switching lifter," explains Meagher. "This differs from a normal lifter in that there is an inner body and an outer body connected by a spring-loaded pin. For V-8 operation, the pin is fully expanded by the spring so the two pieces act as one and the lifter acts like a regular lifter. When we want to disable the valve operation, we deliver high-pressure oil to a groove in the lifter that leads to the outside end of the pin, forcing the pin to collapse the spring. Now the two parts of the lifter are free to move relative to one another and as the cam lobe pushes on the follower the inner portion of the lifter pushes against another spring at the top of the lifter and does not transfer force to the push rod."
Info above copied from this article--->GM displacement on demand technology