Gears grinding when changing ratios - KZN130

[bronx89]

Is this normal on "older trucks"? It is a 1995 Surf 1KZ KZN130. Automatic. Happens going both from N to Hi and N to Low, but not every time, sometimes it goes in smooth as silk.

Doesn't grind/crunch all the time, seems random when it does/doesn't. Always either come to a complete stop before changing or slow down to a slow roll of about 1-2kmph have it in N.

It reminds me of when you change gear on a manual with a syncro that is a bit rooted, a quick short sharp crunch/grind but she is sweet going in and out.

Anything to be worried about? Is it "normal"?

[Sadam_Husain]

yeah mate its normal there isnt any syncromesh in the transfer box, come to a complete stop, dont force or rush it and it'll change fine, try and rush it and it'll grunch

[bronx89]

yeah mate its normal there isnt any syncromesh in the transfer box, come to a complete stop, dont force or rush it and it'll change fine, try and rush it and it'll grunch

That's the thing though I never rush it, always do itnas slow as possible, always came to a complete stop but in the weekend had someone say that sometimes a slow roll of 1kmph or so helps.

If I am stopped and doing it as slow as possible and it still crunches what domyou reckon the prob would be? Would being low on oil cause that?

[Sadam_Husain]

your over thinking it mate, go back and read my first post and stop reading after the bit that says yes its normal


no syncromesh means you'll get a grunch

[jonossiksilvia]

Are u leaving the auto in gear? I either put auto in n or p and do it. I havnt had any grinds doing this way.

[bob_or_jim]

jonossiksilvia is correct. When you have the auto in N and nothing holding it back, it will slowly turn. Its just the movement of the oil in the planetry gear set making it rotate. If you put it in P and have come to a stop you will be sweet. In saying that it will be fine with a little cluck as it goes in.

Cheers

[bronx89]

I always have it in N, haven't tried P. I have stopped every time bar once this weekend just gone to see if it helped. Seems to crunch randomly stopped or crawling.

And I did read your first post mate, you said coming to a complete stop and doing it slowly will rid the crunching - however that is exactly what I do and it still tends to crunch 50% of the time.

So, bob_or_jim, is it better to change between ratios in P then? Will try that from now on. Annoying having to stop when all the manual guys keep rollin on haha

[UBZ]

the 130 ADD transfer case does have a synchromesh setup in it .
you are supposed to be able to go from H to L and L to H at low speeds .
if you read the owners manual it explains all this .

It could be a few different things .

the Auto could be dragging due to dirty trans oil
the transfer case oil could be low or contaminated needing to be replaced .
the ADD system or computer could be playing up , its common for the actuator solenoid and wiring on the rear of the transfer case to get beaten up off road .

Also due to the ADD system as soon as you engage Low , 4wd is engaged as well.
So it could be front diff related as well .

I would put the truck up on 4 jack stands and carefully engage drive , then have a good listen underneath as to where the grinding is actually coming from .

[bronx89]

Yea I was aware you are supposed to be able to change between them at low speeds. Ok I'll try locate where the noise is coming from better when I can, but I'm pretty sure I can feel the crunch through the stick as well as hearing it. Auto oil is new. Transfer case oil I haven't touched yet.

[Crash bandicoot]

you wont get from 4H to 4L on any transfer case without a grind whilst moving, the change in shaft speeds is too great not to.

2H to 4H yes not an issue.

even with a auto trans in neutral as above the residual flow of oil will still let the planetary gears rotate from the torque converter to the shaft between the trans and torque converter. the only way to make it stop completely is to place it in park to lock the output shaft.

however in saying that it will still give a grind if there is any tension on the drive line say parked on an incline

[bob_or_jim]

I guess it is better but mine always gives a clunk or two. Not too worried about it. Like you say stopping is a pain . I wouldnt get too worried about it mate, it means your getting out and using it so clunking is good

[jonossiksilvia]

you wont get from 4H to 4L on any transfer case without a grind whilst moving, the change in shaft speeds is too great not to.

2H to 4H yes not an issue.

even with a auto trans in neutral as above the residual flow of oil will still let the planetary gears rotate from the torque converter to the shaft between the trans and torque converter. the only way to make it stop completely is to place it in park to lock the output shaft.

however in saying that it will still give a grind if there is any tension on the drive line say parked on an incline

As above. Only time I've had trouble was when under tension in park. I leave foot on brake hard, put into park and move transfer. Can do in neutral also but moving forward very very slowly without coming to a complete stop

[bronx89]

Oh yea she definitely gets used haha. Sweet cheers fellahs!