diff noise while coasting??

[BBVX]

OK, for the gurus...


What's wrong with my front diff? On the highway, at anything over 40 mph, when I take my foot off of the gas we hear a grinding sound coming from the front end. When I put my foot back on the gas, the sound stops.
So, I'm assuming that for some reason, the gears in the diff aren't meshing together correctly. Is this right?? Is my backlash setup wrong??

Thanks,
Brian

[SGT.BATGUANO]

Could be.........or cv's or bearings.

[Andrey]

Brian, are you sure your "big meats" are inflated did you re-pack bearings at 30k ?

[Tone]

TOD is the more likely cause - I have had 3 replaced for excessive noise just as you describe. If you disconnect TOD, you will be able to see if the noise goes away or even take your foot off the gas pedal. Others have had rear diffs make similar noise on the highway.

[PeteVX]

talking of driveline noises....

at about 60 mph i hear a whine coming from the driveline, seems to be more towards the rear of the car, as i feather the gas pedal it goes away when i back of and comes back as i put gas back back on again. it goes away alltogether at about 70mph and cant be heard at 50mph either.

I have 42,000 miles and am i think the 3rd owner, i've been meaning to call isuzu and see if its covered under warranty but havent had chance yet.

Anyone have any ideas?

Pete

[t2p]

PeteVX:
.
My VX does exactly the same thing. 38K approx. I'm not worried - I suspect this noise is common.
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However, please inform me if you discover otherwise.
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btw: The trans, transfer case, and front and rear end fluids were recently changed and the 'noise' remains.

[Raque Thomas]

Pete & T2P - I have exactly the same noise at the same speed range - my VX has 22,000 miles on it, and did not make this noise until recently - as soon as I get some time, I'm going to schedule an appt to have it looked at - I'll let you know the outcome.

[Triathlete]

BBVX,
Mine does the same thing though I would say its more of a humming noise than a grinding. Mine started after my lift was done. I know of several other lifted VX's that expierience the same thing.

[SPAZZ]

front pinion nut coming loose?????

[Bobster]

OK Let me get in on this one too. I first noticed the an extra transmission like noise while coasting over 40 just a few days before this issue was first posted. I have to turn the sound system below "normal" listening levels to hear it. But, it's definitely a new sound. I am at 20,000 miles on the odo. The front and rear diff and transfer fluids were changed at 15K dealer service.

Guess its truck?? And trucks make a lot of funny sounds??

[yal^]

I got the same grinding noise after my lift. Actually it wasn't so bad before I got alignment, but now I even get bad vibration in my floor. It kicks in after I reach 40mph and its either when I accelerate or let go of gas. I noticed it's happening only around certain rpms - or maybe it's my imagination trying to put one and one togheter?
I took a mechanic for a drive the other night, and he suspects drive shaft rubbing somewhere. I was thinking I had a broken motor mount after my last off road adventures, when I tried to see if VX can balance on its nose LOL
I have an appointment with Isuzu service, so hopefully I'll get a few answers. What I think though, maybe 3" lift is too much. I have 912 OME springs and 1" coil spacers. Maybe there is problem with CV angle?
I doubt it's differential - I just got it serviced, and it was absolutely fine...
I'll keep you posted on what dealer said.

[t2p]

yal - well of course your differential is fine ........
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maybe the tires should be balanced again ........ ???
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CV joint ........ ???
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could also be a sign of a driveshaft u-joint going south .......
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or an issue with a driveshaft slip joint ???
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a driveshaft may also be 'dinged' a tad ....... be out of balance .....

[t2p]

btw: The trans, transfer case, and front and rear end fluids were recently changed and the 'noise' remains

.
last evening - and again this morning - I did notice the slight noise is not as noticeable ........ so maybe the fluid change(s) did make a difference ......
.
again - I'm not too worried ....... although the VX is not as quiet as the Ford Explorer we have (that also has a Borg Warner transfer case), it is MUCH MUCH MUCH quieter than some of the 4wd vehicles we have owned in the past - and we never had an issue with those vehicles ............

[PeteVX]

Isn't it funny how you mention something that you think is just happening to you, then you find out a bunch of others have the same problem?

Boards like this are the best thing that ever happened for enthusiasts!

I plan on calling Isuzu today to see if mine is under warranty then i'll get it in, it'll be interesting to see if we all get the same diagnosis.

Pete

[BBVX]

...just returned from the dealer. My new rear diff will be in on Tuesday.
It sounds like this is a pretty common occurance with the VX. I'll be making sure to pay extra close attention to it from now on, assuming this fixes the problem.

Thanks to all,
Brian