I have a 2000 EB 4x4 that does the grinding during slow turns. It usually happens when warm. I plan to change out both front and rear differential fluid, and have purchased the necessary gear oil and friction modifier for the rear. However, as I understand it, the problem really stems from the rear clutch packs, and since the fluids are so expensive (about $150 Can.$$) I wonder if I should just have the clutch packs replaced now, rather than having to buy the fluids twice.

Has anyone had any sucess in ridding themselves of this hideous noise by just changing the differential fluids?

 

it's possible, if someone changed the oil without putting in the friction modifier, sometime in the past. Beyond that, I couldn't say.

 

Usually, when the clutch packs wear out, you just lose any "limited slip" functionality. A grinding when turning indicates that the clutches are grabbing. If this is the case, then fresh fluid & friction modifier will help. You really won't know until you pop the cover and take a look in the housing to see what's going on.

Maybe grab enough "cheap" lube to get your Expy to the shop IF it needs work. If you don't use it, return it to the store.

 

Thanks NoMo. I was not going to take the cover off unless I had to. My plan was to suction out the old and put in the new. From your reply, it is likely a good idea to take a look inside. However, I am not sure what I would be looking for in terms of wear and tear. Do you think it is worth trying the new fluid and modifier or just take it to the dealer and let them have a look inside? I am not very trustful of dealerships and these expeditions seem to be so finickity that I am concerned about taking it to a general repair shop.

 

It is definately the fluid. Mine started to do this a 20K miles after I had the fluid changed by someone who I know did not use the correct fluid and friction modifier. When I changed it out myself with the good stuff (ain't cheap), it works perfect.

 

Since you're having an issue, I'd pull the cover off and see what's going on inside.

There should be some really fine 'sediment' from gear break-in and clutch wear. This is all normal. However, if you see an excessive amount (more than a tablespoon?) or any larger shavings or chunks, then you should have the axle checked out by a pro.

 

Thanks to those who have replied. I will get a gasket tomorrow, take a look, and if all is well, put in the good stuff. If it looks bad, I'll put in the cheap stuff plus modifier (not too expensive, but smelly) and limp off to the dealer.

I'll post the results when finished. Thanks again.

 

Unless the truck is still under the terms of a factory warranty, I would avoid the dealer and try to find a reputable specialist to install a good aftermarket limited slip system.

 

How often should the fluid be changed out in the rear end? I know the Maint. manual mentions never to do it, unless the rearend has been submerged under water...

 

I don't know the correct nswer to your question. Ford service says it does not have to be changed, unless as you mentioned it has been submerged. However, my EXPY has the clutch pack problem that seems common to these trucks. I have about 125,000 miles on the vehicle. This mileage and the fact that most of the threads on this site seem to indicate that a fluid change helps has prompted me to change the fluid. Perhaps if I had done it earlier I would not have ths present grinding during low speed, sharp turns. At any rate, the only reason I can see not to do it on a periodic basis is the cost of the oil.

 

i have a 97 exped. i think i am havin the same problem
it only happens after a highway run of 30 mins or more
does the truck shudder and make noise in the rear of the cargo area???

thanks jay

 

I did not have any noise in the rear, just from the front. According to the threads I have read, this is the way the rear differential problem presents itself. I have changed out the fluid, but it has been so cold and snowy here I can't tell if the problem is fixed (it only happens once evrything is good and hot).