Jet engine noise from rear diff...
 

The truck is making a loud whining noise. It sounds like it is coming from the rear diff. The whine occurs during acelleration and decelleration with the truck in gear (I've got a stick shift) and gets progressively louder at higher speeds. I tried investigating last night, crossing my fingers that it may only be low on oil. Once I crawled under the truck, I noticed a whole lot of oil around the diff breather. Basically the whole side of the 3rd was covered. I wiped off most of it on and around the breather, and made sure it the cap was free of gunk and loose. Then it was onto the fill plug. I cannot for the life of me get that damn bolt loose. I've doused the thing in Releaseall, and used a nice and long breaker bar to no avail. I sprayed the thing with more Releaseall, and after work I'm going to attempt to get her loose again. What a royal pain in the arse! The whine is just as loud as it was. I do seriously hope it is just low fluid, because I really don't have the facilities or tools at the moment to attempt any serious repairs. Rock on :banger:

whine like that means toated rear or at least bearings

ya find an impact thats really the best way to budge a stubbern fill nut.

yep, that whine is a telltale sign that you might need a new 3rd member! fortunately if worse comes to worse, you can pick one up for $100 or so with stock gears.

you want a 6 point 24mm socket for the fill/drain plug. harbor freight sells a 1/2" drive 6 point impact socket set with sizes from 24mm down to 10 or 12mm or so for about 8 bucks. well worth it, considering that craftsman only sells a 12 point(good for rounding bolts) socket in that size, and it's $6 by itself.

Well, that bites the big one. Definately not the news I wanted to hear. I don't have access to any pneumatic tools either. I guess the only solution is to crack the cap and take a look for myself. Not having a garage bites. How would I differentiate between the 3rd being toast or just the bearings? This isn't something I have ever done before, so I am a little scared of doing it myself. Also, I am sure that this is something that needs to be done as soon as possible, but how long would I be able to put it off for? I don't drive too much at the moment, but I wouldn't get a chance to work on it until next weekend so that still would mean roughly 100kms or so. Should I just park it? Also, is there anyone in Calgary that would be willing to give me a hand doing this? I don't mean doing it for me, but more like someone who has done something like this before and knows what they are dealing with, unlike the total newbie I am to this sort of work. :banger:

Check the fluid levels before driving any farther. If it's just fluid, (unlikely), you may avoid more damage if you fill it. However if it's fluid, there's a reason it was low. So, either way, it looks like you are gonna have to get inside it and see what's what.

Mike in AR

hey your better off than me, my girlfriend is picking up my truck from the shop$1,400......bearing and seal both sides for the rear and new drums and shoes, and some inner axel rod thing....last time my bearing and selas on one side was almost 700 so i think it is worth it, got a warrnty and confidence that it will last

It's probably not just the fluid in my opinion. Oil coming out of the breather means either there is too much oil inside, water is raising it up (which would come out milky), or the oil is boiling inside due to heat. My guess is that the bearings are going out and the oil is boiling out.

There is nothing I couldn't undo with a good breaker bar and cheater bar given the space to have a good swing. Still, an impact may be necessary if some gomer put the hurt on it when tightening it up.

I think your best bet would be to get a new rear end if you've never set one up or repaired one. You need the right tools and knowledge to inspect and set up gears properly. You'll also have to inspect the housing. It's not difficult once you know how to do it, and on Toyotas it's pretty easy actually, but I would not recommend the job if you have limited experience. My advice would be to get a whole new rear end, or take the whole axle into a shop. Good luck.

It's the rear end, prob easier and cheaper to get another one from a boneyard, rebuilding will cost you way more...

Thanks for the input guys. I managed to get that damn bolt off, and sure enough I was quite low on oil. I topped it off to the hole, but I didn't have a chance to take her for a rip. I will let you know if it actually did anything, or just delayed the inevitable.

Well, oil is topped off. It didn't help one bit. It still sounds like an airplane. I am trying to figure out my options now. I could take it in to get it rebuit, but it seems that your guy's general opinion is that it'll slam the wallet hard. You've also said that it would be better for me to just pick up a rear end from a boneyard. Any idea how hard it would be to find a stock 4.56 rear end?

check www.car-part.com for the 3rd. member or ebay.

Ok, so an update. I decided enough is enough and so I took it to the stealer to get them to check it out. They tell me the carrier is shot, and that they can't find anything cheaper than 1600 bucks canadian. I basically gagged on the phone. I'm picking up the truck tonight. The arb air locker seems a heck of a lot more interesting all of a sudden, considering i can get it for half the price. yeesh... anyways, if i do opt for the locker i wont be able to afford the air compressor for a few months. Anyone have feedback on installing an arb air compressor in the cramped confines of the 2nd gen 4runner?