whinning in 3rd and 4th

[patjamejam]

Ok todays issue is a whinning sound has developed... it seems like from the rear end but only starts in 3rd and 4th at 40+mph....? Just wondering rear end....trans or what this could be. Seems to be ok (no whin) in 1st n 2nd gear

Basicly coasted home, in coast mode there was no whinning... any idea's???

thanks

[5thhorsemann]

Sounds like a ring and pinion issue, only happens under power. Check your jackpot lube, if it is really low it can cause this.

[patjamejam]

5th Thank you......but Jackpot lube?......is this rear end oil? If it is I love the term.

please clarify

[5thhorsemann]

5th Thank you......but Jackpot lube?......is this rear end oil? If it is I love the term.

please clarify

Yea, differential, rear end, whatever. If you ever have the misfortune to have a bearing or gear problem within that pretty little casing, the "jackpot" reference will become clear. They are a PITA to set up.

[Arne]

I tend to disagree. If it is gear specific, I'd lean towards the transmission. Differential noise will be road speed tied, and which gear will make no difference.

[patjamejam]

arne....interesting..when i pull her out of gear at 60mph+ no more whine.

[Arne]

arne....interesting..when i pull her out of gear at 60mph+ no more whine.

That may or may not point to the transmission, as there's no load on any of the suspect parts when it is out of gear.

More telling is that you say it does not do it in 1st or 2nd, but does in 3rd and 4th. But even that can be deceptive, as if it only does it under load, it may not be possible to get it loaded hard enough in the lower gears to hear it.

Here's one of the things I'd listen for—in third gear accelerate and listen to the noise, then shift to fourth and continue accelerating. If the noise changes significantly from third to fourth, it is probably in the transmission. If the sound has the same basic note in both gears, it could be either the tranny or the diff.

Your profile doesn't say where you live, but it might be helpful to have a different set of ears listen to it.

Edited March 26, 2011 by Arne

[patjamejam]

I live in venice, ca.

The sound changes pitch from 3 to 4 and is worse/louder in 4th. The only shop(MIKE's Z) I've used is 45 miles away....They rebuilt my 4speed 8months /3000miles ago so in a way I hope it is the tranny

My plan, check rear end fluid....then if still bad... off to the shop she must go.

[olzed]

My bet is Gearbox/ transmission bearings. Unscrew the bung from the bottom of the tranny and let some oil into a clean container. Just a little. No need to drain it all.(You may get some up your arm) Whack the plug back in. Check the contents of your container for metal particles. The oil should be spotless. If not----

Brian