LR3 slight differential noise normal?

[RAJOD]

Thanks anything I can bring to my mechanic the better.

I took another look at the dealers records on the car. I found this passage in one of the repair pages.

I see he had both front hub and bearings replaced and it said topped off all fluids and lubed.

Its said "customer advised some differential noise noted"

I could find no repairs for differential fluid unless "lubed" means they changed the differential fluid.

I mean the guy has all this expensive stuff replaced on it so why would they not just change the differential fluid if it had a noise? I'm not sure if they did or not.

 

[RoverGuy7]

I doubt they did if there isn't a specific line and labor for it.

Also, generally speaking, drive line fluids are not included in normal 'fluid top offs' as there is no dipstick, the diff fluid level cannot be checked without draining them out, and the transmission can not be checked when hot.

 

[RAJOD]

So is new fluid the cure for noise in the differential?

Does that mean its run dry or something?

 

[RoverGuy7]

Dave, what do you think about using an 85/140 for a little extra wear protection for those diffs?

I haven't tried it, I personally just recommend frequent, fluid changes. My father has an LR3, and I make sure he gets it changed around every 30k, probably overkill, but peace of mind to me. Once the noise starts, a 140 weight may help, as it is usually a gear noise that may get somewhat muffled. However, with as little fluid as these hold, I prefer to have a 'lighter' fluid in there, more viscous fluid will cool much slower, and you don't have a large quantity like in a solid axle car to aid in that. This is pure speculation, but I could see a heavier oil causing bearing issues over time.


Also, no, changing the fluid is not going to 'fix' the noise, I don't believe anyone said that at all. It may help, especially if your fluid level is low, or you have a plugged up vent (if it's under pressure, you need to fix the vent, search the forum for information on that) but the fluid is not causing the noise, gear wear is causing the noise. I doubt that it has been run dry, as then you would have a horrible bearing noise constantly, not the gear noise that you are hearing.

 

[RAJOD]

Thanks for the information.

Just wondering why a beefy truck would have so many issues with differentials. My Explorer and other cars I've owned in past 30 years have never had that sort of issue.

Must be some kind of engineering error for so many to have noise. I mean sure a cheap yugo or kia might have issues at 80k but a road only driven tank of a car like a LR3 well you would just think that would never be an issue like it is.

Yes thicker weight oil probably would cut the sound some. Just like STP use to do for rocker arm sounds.

 

[Mack73]

The theory is that a coating was applied to the inside of the diff housings. This coating flakes off and becomes junk that gets run through the bearings over and over again.

A flush gets rid of any contaminents. Also since the volume is on the low side, frequent changes wouldn't be a bad thing

 

[jwest]

If I said 90k for the diffs and t-case I mis-spoke.

I recommend front and rear differential fluids, be it locking or open, at or before 75k, along with the transfer case.

The transmission fluid I recommend starting to change out around 90k, spec is 150k, and pretty low failure rate due to fluid itself, so that's not as urgent, I wouldn't push much past 120k though, but change the diff and t-case fluid soon.

This sounds like very good preventative maintenance to do early. I doubt it cost much to replace fluids early compared to wearing things out early.

Any ideas on average cost to do all of these?

So 3 specific items:
2 diffs
transfer case

Anything else while in there? I'm getting the oil changed Wednesday.

Mine are all covered up by the 2 Rasta belly pans front and middle.

Thanks for posting in the forum!!

 

[Houm_WA]

I'd have to look but I bet $150 per item is a good estimate....I have the same skids as you, too, Jwest.

 

[jwest]

cool. Hey, guess what, it looks like RS sliders do not fit over the newest air compressor too well! The new one is deeper but it also seems to be more robust for protecting itself with a really thick aluminum plate around and below it.

I'd just have the sliders modified but damn, I already had them blasted, galvanized, cured for 6 months, then recently powdercoated! ARGH!

Houm: do you have or know of a local tire size used off road thread? I'm trying the 32" GY Duratrac and have some user data. I'm undecided overall on fit trade offs other than the tire compound and tread pattern seem "better" than the BFG.

 

[RoverGuy7]

With extra skid plates I would have to see it before I quoted a price for sure. But with the skids that I have seen, I don't think I would charge more the 2 hours labor to change out the drivetrain fluids(never done specifically that alone on one with skids) And the fluid itself is not too bad, my shop uses Motul 75w90 in the front and rear differentials (add BG LSii as friction modifier for locking rear) but we use the factory t-case fluid, I do not recommend using anything else, even though many have, and several syn. ATF do 'crossover as compatible' All together parts total to about $85 or so, plus the labor.

The transmission gets more complicated. To start, if a shop tells you that they can do a transmission service while you wait, for less then 4 hours, they either are lying to you, or not preforming it correctly. I do not trust any fluid exchange/flush system that I have ever seen, or used, and the fluid MUST be filled with the vehicle cold. Also, if you plan on changing the filter, it is several hours of labor, as exhaust, frame cross beam, and engine mount need to all be undone before the pan can be removed.