2001 Pathfinder 4x4 LSD rear end problem

[amb4081]

I have an 01 Pathfinder LE, 4x4 (electronic) with rear LSD. I've recently noticed a whirl/whine noise from the rear end when under acceleration from 45mph-55mph. Below and above that range the noise is absent or almost absent. Also, it only occurs when I am accelerating. If I let my foot off the gas, the noise immediately disappears until I press down again on the accelerator. Again, this isn't under HARD acceleration. This occurs with the slightest pressure on the gas.

I recently changed the differential fluid, hoping the noise issue would be resolved, but to no avail.

Also, I notice the noise more when the outdoor temperature is warmer. During cold days, it will not make noise until the vehicle has been driven for a few minutes.

Any input is appreciated.

I don't know if it's driveshaft or differential related, or wheel bearing.

Thank you for you responses.

[NISTECH]

Tall tale signs of ring gear or pinion gear wear. They are the main drive gears in the diff. You could repair it with new gears but it requires some knowledge/feel for building diffs. However it would likely be more cost effective to just replace the drop out diff.

Your looking at $850 for the drop out unit, plus the like around 3.0 hours labor to install it.

If you have it rebuilt overhaul time is around 7.5 hours. and parts will be very close to the whole unit cost. You would need bearings and other misc parts typical of a diff overhaul. the pinion set alone is about $575 thats without the bearings and such.

[amb4081]

Thanks for the evaluation, Nistech. What kind of time frame do I have? We're going on vacation in a week and a half. We're planning on driving the Pathfinder. Will it be safe for the trip?

Also, is something that needs to be nipped in the bud early to prevent further damage, or is it something fairly isolated to itself? I'm trying to figure out a time table on how soon to fix it. Thanks.

It might be too big for me to handle. The most complicated task I've performed is replacing the timing belt on my wife's 91 accord and full suspension replacement on a couple of cars. I do have the FSM (cd) for the Pathy. I'll look at it later. Will the differential section of the FSM be detailed enough for an amateur/novice to work on it? Thanks.

Does the whole diff. have to be dropped, or a sub-assembly within the diff case? Thanks.
Modified by amb4081 at 5:17 AM 5/3/2006

[NISTECH]

The problem is isolated to it self. I really cant give you a time frame. You could drive it for quite some time without complete failure. At this point its more of a annoyance then anything. On a long road trip that can get pretty irritating..lol. The diff removal on your vehicle is pretty easy by comparison to a t-belt job. You simply jack the rear end up, remove the rear tires, remove the 4 nuts holding the axles to the housing at either end of the axle tubes. slide the axles out about 2 or 3 inches. Remove the drive shaft from the diff pinion flange. remove the 12 or so nuts holding the third member into the diff housing then gently slide the diff perfectly straight off the studs. Clean the gasket from the diff housing. wipe clean the inside of the diff housing of all old oil. [be sure to drain it before starting disassembly or it will be rather messy.] Install your new gasket, slide your new drop out in and reassemble in reverse order.

Sliding the axles out of the tubes removes the axle splines from the diff in the center. You only need to pull them out enough to allow the diff to slide out. might be slightly more then 2 or 3 inches.The third member is very heavy as you will see if you buy one to install yourself. So use a floor jack to support the diff as you work it of the studs.

[Joe99qx4]

Hi amb4081

I know this post is only 6 years old (LOL), but I was wondering what your experience was with this issue? Did you let it go or did you fix it? I have the same issue and any information would help.

[4x4pathy]

Well, this is amb4081 under new username...

Anyway, I actually have not done anything to the rear differential besides changing the fluid 2-3 times since owning it in late 2005. The rear end noise is still present but has not worsened to date. It is still more noticeable in warmer weather but driving has not been affected negatively by it. And we have put nearly 80K miles on it since owning it; we're at 185,000 and still going.

[Towncivilian]

Welcome back.

Well, at least your noise isn't as ominous as it sounds! Stay on top of fluid changes (every 30k miles should be a good interval; change more frequently if towing, off-roading or water entry is possible) and you should hopefully be good for another 80k miles or more.

[4x4pathy]

Thanks, Towncivilian.

I hope to keep it for another 80K or even more...especially since I invested so much time and frustration in changing the alternator last week. What a nightmare!!! Viritually no access to the thing.

[ianh]

My 2003 non-LSD has a clunk due to lash being loose since i got it at 25K miles and 15 months old.
Doesn't change, and its not broke......