So... my trusted shop changed my driveline fluids but used the same Redline 75W90 in both front and locking rear.
I brought to their attention the rear should have been BOT 720 or equivalent and they agree, but instead of offering to change change it out completely, they want to add Redline Limited Slip Friction Modifier.
I'm not sure that this would meet specs because I can't find any info whether that product is suitable for the carbon type clutch in these diffs.
I have a request out to Redline, but wanted to get some opinions from the forum too. Any ideas folks?
I'm ready to go to the mat insisting on a full flush and change if needed, but if the Redline modifier does the trick, that's fine as well.
thanks.

 

HELL no....don't do it. They messed it up, so they need to make it right.

Do you really want to run the risk? That locking diff would be really expensive to replace, and it sounds like you would need to find a new shop to do it!

 

To houm_wa's point, dropping a diff -- let alone rebuilding the clutch packs -- is a hella-ton of work, requiring removing the exhaust, partially freeing the rear knuckles, removing the half shafts and then dropping the diff itself which is like 80-100 lbs and doesn't lend itself to easy manipulation. When I had mine rebuilt, the closest shop I could find that was experienced in the job was ~1,300 miles away in Florida.

 

The shop is on the hook.

You wouldn’t get on an airplane that used the wrong lubricants. No one would allow it to fly.

For this automotive shop to attempt to fix it by adding a $10 additive and not providing specs…huge red flag!

Go to the shop and while you are there call your local Land Rover dealership ask for the service manager, tell them what happened and ask for their recommendation on what said shop should do, or what the dealer would do to fix the issue.

The dealer will tell you that the shop needs to do the job properly with the correct fluids that meet the correct specs. They should also flush out the incorrect fluid. The shop is liable for any damage because they did something incorrectly.

There is a reason for fluid specifications, and not just opinionated conjecture as to whether or not it is necessary or someone believes it meets specs.

I used to work as a technical lubricant sales rep for ConocoPhillips and had a “mechanic” at a clients industrial wood chip yard throw engine oil into the diffs of Cat 787 Mining Truck…

I was nowhere near that client’s yard but my phone exploded with calls and emails and BBM’s

Long story short, I was there in 25 minutes and so it began with the mechanic…

“Oil, and your product is ****e!” Was his excuse…

Said mechanic caused an epic failure in the front differential and cost the company $7 million dollars in lost sales for being down for a week while the replacement was barged up and cost $250,000….

So his first mistake… not reading the pails and realizing he was using 5w30 engine oil…

No friction modifiers and that oil had zero viscosity under that pressure and heat.

You paid for their expertise and they made a massive mistake. To right it, they need to drain the oil and put the proper fluid in, run it, and drain and refill again. It is an expensive mistake for them… AND IT IS THEIR MISTAKE!

Also, this thread gives you an explanation and possible GM substitute that is identical.

 

Thanks for the replies, I agree completely and the shop has ordered the LR-branded fluid and is taking care of it for me next week.
FWIW, I heard back from a rep at Redline who claims their 75W90 has friction modifiers in it.
I specifically asked about it being carbon clutch multi-disk compatible so now I don't trust Redline, either. Sounds like it's just a standard additive.
The LR3 locker is certainly special, but for these people to not know just how special is a problem.

 

I'm curious what shop that was, if you are in the Seattle area. I'd want to add them to my "avoid" list.

 

I'll DM you

 

Bot 720 has not been made for years. And its been discussed over and over, the GM fluid works fine. GM 92184900 It is designed for carbon clutches, used on the GTO or something. $22/quart on Amazon. No need for LR stuff.