Lube for rear differential/axle?

[slingworks]

I'm planning on doing some fluid changes on my '05 Liberty and will be starting with the rear differential.

I'm mainly curious what's available for heavy use? Heavy like "severe duty"?

It's a mail vehicle and sees endless hard takeoffs from a complete stop. Hundreds a day.

In a 3 year period I went through 3 axles, each lasting about a year. (First 2 were professional shop rebuilds and last was a low mileage replacement).

I just installed a "new" low mileage rear axle and would like to keep it from wearing out as long as I can. (It's pretty tight).

I started out with the spec'd 75w-90 and on the last axle I ran 80w-90 (Had some left over from a tractor change).

What's available as a severe duty lube? Just thinking that might prolong wear.

 

[uss2defiant]

85w-140

 

[KJowner]

An axle a year! Are you racing against Ferraris?

 

[slingworks]

An axle a year! Are you racing against Ferraris?

LOL I wish I was able to do that actually.

It's just the limits of the axle design I guess. I probably put more strain on a differential in a year than most see in a vehicle's lifetime. Same deal with U joints.

I've never worn a differential out to the point of outright failure, they just get really loud/hum and end up with allot of slop.

I have somewhere around 360k on the clock on the Jeep. 100% is mail route.

I think it's a fairly common problem, the LLV's the post office has used for the past nearly 40 years is built on on the Chevy S-10 and they rebuild ALLOT of rear ends.

 

[u2slow]

Thicker lube protects better where high heat is generated. Without the high heat, it adds resistance, and may not flow as well.

I have been into the KJ's rear end for 3 times in 318k (km), and each time it's the pinion bearings going south. The 2nd time I changed all the others too - just because. No expired r&p's or axle shafts.

 

[Robochop]

I'm planning on doing some fluid changes on my '05 Liberty and will be starting with the rear differential.

I'm mainly curious what's available for heavy use? Heavy like "severe duty"?

It's a mail vehicle and sees endless hard takeoffs from a complete stop. Hundreds a day.

In a 3 year period I went through 3 axles, each lasting about a year. (First 2 were professional shop rebuilds and last was a low mileage replacement).

I just installed a "new" low mileage rear axle and would like to keep it from wearing out as long as I can. (It's pretty tight).

I started out with the spec'd 75w-90 and on the last axle I ran 80w-90 (Had some left over from a tractor change).

What's available as a severe duty lube? Just thinking that might prolong wear.

While it calls for the 75-90, I always like to use the synthetic 75W-140 with no issues, but I don't drive it as much as you do! I always use the differential cover gasket as well. The RTV everyone uses is messy and very hard to clean as well. Amazon and eBay have them and they are under $10. You sure have gone thru a lot of axles, have you tried getting another rear-end from the junkyard or something? Good luck with your project!

 

[always wrenchin]

Get a Lube Locker diff cover gasket. They are reusable. And change the fluid often. 75W140 if you are not in too cold of a region.

 

[OK-J]

I highly recommend using Redline fluids. I have used Redline products (including their 75w90) for years - and though I maybe not as extreme use as you, I have towed, etc with mine. I was introduced to Redline products when I worked in an auto parts store 25 years ago. Redline uses a purer base stock when refining and I think it shows. Different testimonials of their products over the years from customers etc. have been very positive, and I have not seen it let me down. Worth checking out.

 

[slingworks]

While it calls for the 75-90, I always like to use the synthetic 75W-140 with no issues, but I don't drive it as much as you do! I always use the differential cover gasket as well. The RTV everyone uses is messy and very hard to clean as well. Amazon and eBay have them

Get a Lube Locker diff cover gasket. They are reusable. And change the fluid often. 75W140 if you are not in too cold of a region.

I bought some 85w-140 this evening. I'll know in a year or so how it worked out!

 

[slingworks]

While it calls for the 75-90, I always like to use the synthetic 75W-140 with no issues, but I don't drive it as much as you do! I always use the differential cover gasket as well. The RTV everyone uses is messy and very hard to clean as well. Amazon and eBay have them and they are under $10. You sure have gone thru a lot of axles, have you tried getting another rear-end from the junkyard or something? Good luck with your project!

I've got a nice assortment of worn out axles sitting in the yard. One was rebuilt at least twice that I know of (probably quite a few times?) and a couple used axles that gave out. I feel like the rebuilds didn't last a whole lot longer than the used axles overall.

Yeah that's crazy really. I've heard for years that Jeeps don't hold up on mail routes. Even though that mostly applies to Wranglers I'd say it applies equally well for my Liberty as well. My wife has (had) a normal LHD 05 just like mine for many years and it held up quite a bit better. Original trans/motor/transfer case/axle etc and it's close to the same mileage. I've started to cannibalize it for parts mainly due to the serious rust situation of the body/doors.

Wonder if those axles have any value for someone else's rebuilds? LOL

 

[KJowner]

What's actually wearing out in the axles? It would be interesting to see what the weak point is.

 

[u2slow]

What's actually wearing out in the axles? It would be interesting to see what the weak point is.

Pinion bearings
(For me anyway)

 

[slingworks]

What's actually wearing out in the axles? It would be interesting to see what the weak point is.

I never actually took the time to take one apart. For me they'd start to get loud and produce a fair amount of vibration. The amount of slop within the differential would also get pretty serious.

 

[slingworks]

I've got a nice assortment of worn out axles sitting in the yard. One was rebuilt at least twice that I know of (probably quite a few times?) and a couple used axles that gave out. I feel like the rebuilds didn't last a whole lot longer than the used axles overall.

Yeah that's crazy really. I've heard for years that Jeeps don't hold up on mail routes. Even though that mostly applies to Wranglers I'd say it applies equally well for my Liberty as well. My wife has (had) a normal LHD 05 just like mine for many years and it held up quite a bit better. Original trans/motor/transfer case/axle etc and it's close to the same mileage. I've started to cannibalize it for parts mainly due to the serious rust situation of the body/doors.

Wonder if those axles have any value for someone else's rebuilds? LOL

I've only used the RTV on the covers so far, but I did use a gasket once when I did a fluid change on the trans. (42RLE). I've done quite a few transmission fluid changes over the years on the Liberties we had as well as my Ram C/V. The pans on those seal up with RTV as well and I thought it might be better to use a gasket, so I installed a gasket once. I ended up regretting the decision. The gasket "vulcanized" to the pan and trans, and I had a hard time getting it off. Ended up bending the lip of the pan in a few places in the process. The RTV at least was easy to get off without damage. Now, I probably used a common Chinese made gasket, so it could have been the gasket to blame........

 

[mercdudecbr600]

Redline full synthetic - they've got HD fluids.