[TrevorStaader]

Hey everyone,

I have had this noise in my sj80 for a month or so now. When i let the clutch out with highish revs nothing happens for half a second then i hear a big crunch noise coming from under neath the car, this also happens when im driving up a hill with decent revs the it takes a short time to kick in and makes the noise. This happens frequently when offroad when the car is under abit of pressure. It never happens in 4th or 5th just when revving it in the lower gears or fast(for a sierra) take offs. I was wondering if anyone else has had this problem or knew what it could be? Any help would be appreciated.

Thanks,
Trev

[atari4x4]

can you film/record it & post the video?

[TrevorStaader]

atari4x4 wrote:

can you film/record it & post the video?

Yeah sure, ill give it a go tomorrow.

Thanks

[atari4x4]

sweet, as you can imagine random noises are hard to diagnose over the net.

[Ace]

"sounds" like a clutch engagement issue. I can only speculate but if there's a delay and bang. If only in 1st to 3rd at revs and no issue above maybe the uni's and/or rear diff - only guessing though

[TrevorStaader]

I tried to record it tonight but my phone has worse recording quality than i thought and sounds nothing like the sound. Ill try to find something better to record it with.

It does sound like its coming from the rear diff but im not 100%, thanks for the help.

[atari4x4]

could it be a dry/sticky uni joint, would probably need to remove the shaft to feel it.

[TrevorStaader]

atari4x4 wrote:

could it be a dry/sticky uni joint, would probably need to remove the shaft to feel it.

Ive never taken the shafts off, ill give it ago. How much play should be in the shafts i can move them a bit back and forth?

[atari4x4]

the uni joint should move smoothly with no slop or notchyness, i guess the splines in the tailshaft would have a bit of play in it.

there will be a bit of backlash in the diff, eg being able rotate it slightly before it take up the slack in the, ring & pinion, sun & spider gears in the diff.

[TrevorStaader]

atari4x4 wrote:

the uni joint should move smoothly with no slop or notchyness, i guess the splines in the tailshaft would have a bit of play in it.

there will be a bit of backlash in the diff, eg being able rotate it slightly before it take up the slack in the, ring & pinion, sun & spider gears in the diff.

Makes sense, ill have a look. Thanks for your help.

[TrevorStaader]

Its been awhile. I pulled the tailshaft out and they seemed alright and went for a quick drive in 4wd with it out and it still made the noise, so took the jackshaft and front drive shaft out (not sure if thats what its called) and it all seems smooth and not much play except in the transfer case it self but. Dad found out that coilys have a chain in the transfer case? and sounds like that? Has this been a problem for anyone else?

[Ace]

Just an idea... how bout giving your mate 3ft of garden hose ( think home made stethoscope) chuck him in the passenger seat go for a wee drive n tell him to stick one end to his ear and wave the free end around to source the noise. This theory works wonders to isolate "noise" on the cheap