Is this normal?

[Mikeys00vx]

Hi guys,

A little of your all-knowingness would be appreciated!

Here goes. When I let off the gas, I hear a humming/whirring/groaning sound like the tranny/TOD is engaged(?) while coasting. Is this normal? The engine RPMs decrease as they normally would when you let off the gas. It doesn't sound like its about to fall apart, but I certainly want to know if its abnormal and needs to be looked at. I've only had the VX for about 6K and I don't recall hearing it when I first bought it. I know the VX has a complex transmission/TOD system and I acknowledge that it could be completely normal.

Have/Do any of you experienced this? Any help?

Thanks,
Mikey

00 Foxfire 30K

[Mikeys00vx]

I checked other threads and see that I'm not the first to have this "problem"! Probably gonna take her in to the local Isuzu dealer and see what might can be done. Getting close to the warranty being out! (titled in 2001!)

Mikey

00 Foxfire 30k

[Joe_Black]

PBR had this problem and IIRC eventually got some differential gears replaced. Typically it's an indication of a gearset that isn't machined properly although failure is unlikely, because the surfaces meshing out of tolerance is what causes the noise. Normal wear would eventually "soften" the noise, but better safe than sorry if you've got warranty left.

[Whaleboy]

my girlfriends vehicross, whenever her tires run low (as she doesn't check them, go figure) her VX begins to do this exact same thing I've noticed. The more pressure, the less noise.

Not that this is your problem, just might be something to check.

[Anita]

I had a similar noise when I let my foot off the gas. Found out it was caused by one of my tires. It picked up a nail and was very low on air.

[Otto]

You must make sure tire ware and pressure is even at all times. If tire ware and or pressure is uneven the TOD thinks your tires are sliping and starts to engage

[PeteVX]

i dont want to sound cynical but good luck getting it resolved!! I've had the same problem for over a year, its been into the dealership over 15 times under warranty, they've rebuilt the rear diff 3 times replaced the front and rear diffs, transfer case, front drive shafts and a hundred other things. The noise is still there, everyone agrees it shouldnt be but no one can fix it. Isuzu are flying out a manager and their best service tech next week to test drive it and try and figure it out.

I think the cost so far from my dealer is in excess of $12,000 and its worse than when they started!

I sincerely hope you have more luck than me but hey, i have a entirely new drive train at no cost!!

Pete

[Mikeys00vx]

Thanks to all the posts responding to my original question. This site is great.

After reading all the replies, I decided to check my tire pressure on the front. The tires didn't seem to need any air by looking, but, my front right tire was considerably lower than the front left tire. Apparently I have a VERY slow leak. Anyway, I put some air in my front right tire, and believe it or not the humming/whirring/groaning sound disappeared.

Thanks for the help guys!

Mikey

[psychos2]

if the gears in the diff are not set up properly you will get a whine. shawn