I decided to go with the fleetguard filter and amsoil synthetic after the 15000 to 20000 mile break in period. How many miles are you guys traveling before oil changes using synthetic?

Also, the maintenance book says to change rear end oil every 15000 miles. I looked and could only find a fill spot. If I remove the bottom bolt from the housing, will this drain the rear end< or must I pull the whole cover off and replace the gasket each time?

Thanks

 

I doubt anybody changes the diff that often but I could be wrong. Yes the cover needs to be removed to drain the oil. This is speaking from 1st gen stuff mind you. I pulled my cover after 175k of unknown service and cleaned it out real good. I have since changed it a couple of times by using a vacume pump directly after a drive so its mixed up and hot. There also should be a magnet inside the cover to catch ant meatl particles

 

I don't think you need a gasket with the AAM axles.

2nd gens used RTV, but I think the 3rd gens have a rubber lip in the cover that acts as a gasket.

I also don't see the point in changing it that often, but it keeps the warranty people happy, just in case.


phox

 

I just did mine at 17k. I noticed that small tubing fits in the fill hole and that it's possible to pump it out, but an electric pump would be needed as the typical pumps for 1 qt bottles only do about 4cc a squirt. I slowly loosened all of the bolts and the oil drained nicely without removing the cover. I'm considering drilling/grinding into the bottom bolt hole, at the end of the threads, so that it would act as a drain plug. Maybe use a bent tab washer that fits over two bolts to keep it secured.

I used Mobil 1 75W-90, and it seems to run a bit quieter, for some reason seems to shift a bit easier from 4th to 5th, but I also might be feeling a bit more vibration at some speeds.

 

Do not buy a new gasket. The gasket is reusable, I have three changes on the factory gasket, and it shows no sign of wear and still seals well.

 

Every 15k sure seems excessive for changing the differential.
Sure it wasn't 15k for a break in change with longer intervals thereafter?

 

The dodge maintenance manual says 15K following harsh conditions, and does not give a time frame for light duty. The owners manual does not differentiate and just says 15k.

 

I just changed the stock fluid out at 8k. I wish I would have done this first change sooner since it looked kinda nasty. I took the cover completely off and cleaned it out out real well, I even jacked up each side of the axle and let it drain. I would suggest doing this at least on the first change. The stock gasket is a nice rubber one that is reusable. I'll be checking and changing my "new" fluid pretty regular, but I'm thinking that 15k is a little extreme.

 

I pull a trailer all the time and I change mine every 30,000 miles, 75-90 syn. oil and have always reused the gasket. I also found to install about 1/4 qt less than what is asked for due to my first change, I had done at the dealer, and they filled it to the bottom of the hole, 100 miles after that I had an axle seal leaking, went to another dealer to get fixed under warrenty, they said it was over full, I told them what dealer did it and showed the paperwork and the tech told me to run it 1/4 less and the problem will be fixed, Have since done it that way and have had no problems at all.
Just a suggestion from them to you all.

 

gofastman gives excellent advice. Most all the leaking differentials I've seen, both front and rear, have been overfilled. Most people don't take the time to read the manual, 3/4'' below the bottom of fill hole in the front and a 1/2'' below in the back, level surface is a must. Overfull also makes the diffs run hotter.

 

Dauntless, you don't have to literally remove the diff cover to drain the oil, just loosen all the bolts on the cover. The weight of the oil will push the cover away from the diff and fall into the drain pan.

When its done draining, tighten up the cover bolts to 30 ft lbs, pump in the good stuff thru the hole and tighten the fill plug to 24 ft lbs. Pretty easy.

Yep, book calls for 15k intervals on diff oil changes.

BTW, I went to Amsoil 15W-40 Heavy Duty Marine for the engine at 18k.

 

I changed my rear diff oil for the first time at 40K miles. It was liquidy, and black. I've got 66K on the truck now. Don't plan on changing it again till 80k.

 

Does anybody know WHY they recommend fluid changes so frequently? My Ford was factory filled with synthetic and was good for 100k miles