Shimming LSD??
Shimming LSD??
Has anyone had any experience with tightening up LSDs? I was told that i needed to sandblast the discs and then fit a 2mm spacer behind the clutch retainer. Has anyone done this? Will it work without damaging anything?? Any info will be greatly appreciated.
***Got the balls, just ain't got the bucks***
ummm sandblasting the discs - don't know what that will do? surely abit of driving around will soon smooth those of again.
Try using the spacer.
I beefed up the preload spring by spacing that out, cause the clutch packs I had looked good for a start. It seems to work ok, I can feel and see it bind and let go when creeping around on full lock slowly - much the same as a auto locka. If you've got the coin throw it out and put in a auto locka - thats what I'll do next time ( I assume you are popping it back in the front?). LSDs will never completly lock (hence the "limited slip" part) and are shockers for not wearing well
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Waterlover ah, looking at that avatar - are you sure about that ?
The LSD i have has only done about 1000km since i fitted it (rebuilt) so one would presume that the clutch packs are as good as they can get. So that leaves the spacers. What size did you fit? i'm also guessing that i would have to reset backlash etc which is not something i have much experience with. Would a dif shop be keen to do this sort of thing. As for the avatar well.......... because of the damage i ended up stripping and rebuilding the truck, new paint and cut down cab. I was fully insured when it happened, got paid out cost of repairs and fixed it myself, so was able to modify truck and get some upgrades for free. Don't know if i'd be keen to do it again though!!!!!
***Got the balls, just ain't got the bucks***
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Steve_t647
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The shim's work by putting more preload on the spring's above standard but as said above it will never be a locker. It depends on what you are after, I have a plan to put mine in the front and have a loker in the back....
Well it is a plan just need time and motivation to do it.
If you want it to be really tight you will still find you loose some power as it is designed to slip not lock also if you are having problems after 1000K are you sure you are using the right diff oil LSD requires LS90 limited slip diff oil.
The difference is roughly this locker is locked unless one wheel is going faster the power goes to the slowest wheel, LSD is unlocked unless one wheel is going faster than the other wheel and as heat increases the lsd becomed stiffer and power is slowly oncreased to the wheel with better grip, most power going to the faster wheel.
Someone will corect me if I am wrong here but this is how mine seems to work, I had an eliptical LSD in a car which worked slightly differently it allowed 3/4 of a turn more on one wheel then locked, but this was expencive and in a circuit and drag car.
Hope this helps.
Well it is a plan just need time and motivation to do it.
If you want it to be really tight you will still find you loose some power as it is designed to slip not lock also if you are having problems after 1000K are you sure you are using the right diff oil LSD requires LS90 limited slip diff oil.
The difference is roughly this locker is locked unless one wheel is going faster the power goes to the slowest wheel, LSD is unlocked unless one wheel is going faster than the other wheel and as heat increases the lsd becomed stiffer and power is slowly oncreased to the wheel with better grip, most power going to the faster wheel.
Someone will corect me if I am wrong here but this is how mine seems to work, I had an eliptical LSD in a car which worked slightly differently it allowed 3/4 of a turn more on one wheel then locked, but this was expencive and in a circuit and drag car.
Hope this helps.
Steve_t647 wrote:
LSD is unlocked unless one wheel is going faster than the other wheel and as heat increases the lsd becomed stiffer and power is slowly oncreased to the wheel with better grip, most power going to the faster wheel.
Someone will corect me if I am wrong here
Hope this helps.
I may be wrong too, but I don't think its got anything to do with heat
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I see it as two clutch packs (one for each side gear) that are not completely locked but are slightly preloaded by a central spring. They're tested by measuring the torque difference between the two axles (which would be hard to judge if heat was involved).
The aim of the device is to lock both side gears to the carrier and this is done by the resistance of the clutch packs aided by the spring (worn clutch packs = no LSD) Also I gather that the spider gears teeth and the way that they mesh against the side gear also aid in forcing out the side gear to lock against the carrier. Sound right
maybe 
From memory the 9 1/4" diff , standard, has a breakaway of 70 to 90Ft Lbs. By trying differant thicknes's shimms you will reach tour required target. Go no more than 1/2mm at a time ,
I have got an old axle, cut it off to 6" long(splined end) and welded an old 1/2" socket to it , fit it into your diff side gear, then install your touque wrench, fit another old axle to the other side, which is held in the vice.
NOTE Breakaway or cracking , is the energy level to start the movement of turning the axle.Which is far greater than the flowing resistance.
Kevin
I have got an old axle, cut it off to 6" long(splined end) and welded an old 1/2" socket to it , fit it into your diff side gear, then install your touque wrench, fit another old axle to the other side, which is held in the vice.
NOTE Breakaway or cracking , is the energy level to start the movement of turning the axle.Which is far greater than the flowing resistance.
Kevin