blown diff

[4runner]

hi all,
my truck started making a funny noise, then it got really bad and i couldn't drive it, so i pulled the diff out, and 4 teeth were missing from the crown wheel,(about 4 months ago i fitted an LSD but keeped the original crown and pinion) i haven't done any hard out driving in it and its a 2lte, i just want to know' is this comon?


picture if you want

[gtblair]

Thats wierd.. The 2lte would have trouble turning the diff let alone breaking one haha!

Who done the diff swap/set up?

[Jerry]

Have you done any recoveries in reverse....the diff design and the 8" diffs are known to do this on occasion....my 2lte pushes mine nicely thank you

[4runner]

i did the swap,parts out of my old v6, i have done some reverse recoverys but not for a long time, just working driving

[Steve_t647]

hi all,
my truck started making a funny noise,

This is when something cracked or broke, it may not have been the pinion or ring geat some bearings may have escaped a LSD on the road would not cause the crack but will put it under a little more stress once it occurs. did you also feel a slight jerk? as it skipped over the missing tooth? when driving?

then it got really bad and i couldn't drive it, so i pulled the diff out, and 4 teeth were missing from the crown wheel,

Either it gave up completely or the spare parts took out the other teeth, how far and how long were you driving with it broken? In an emergency you can push the truck to engage the teeth again and drive it (not nice but an emergency) you will get more and more damage but once rolling and if you are not savage you will most likley get home

(about 4 months ago i fitted an LSD but keeped the original crown and pinion) i haven't done any hard out driving in it and its a 2lte, i just want to know' is this comon?


picture if you want

Reverse is bad because the gear in the gearbox (not the diff) is weaker in toyotas, but you are also working on the weaker side of the pinion.

It is not common onroad with normal driving they fail but they can fail for a lot of reasons but usualy due to stress time and age. With a picture of the damage we would be better able to see what happened also look at all your bearings one of those could have failed to cause the problem with the extra bits in the oil they may fail soon from the bits from the gears.

The LSD alone should not cause this damage all the NZ New Toyotas were fitted with LSD (well this is what they state in Toyota).

Matt4u is running a 5m and a welded rear diff and that thing put's up with a lot of punishment, not sure if he has broken the welded diff yet or not but havent seen anything posted (or have and can't remember).

[Macca]

As said above road driving should not cause problems. I blew 2 diffs within 3 weeksdue to stupid driving and river gravel and i had to give it some serious right boot to do so. When i was talking to people about fixing it i was told this is a common fault in surf diffs as crown wheel is slighlty thinner in front diff and flex's when pressure comes on. This allows pinion to move slightly and engages only edge of tooth and thus breaks it off. good luck with fixing it.
macca

[4runner]

hi all,

it ran out of oil, damaged seal , just thought let you know