[Ramdawg]

My new to me 99 D is coming up on an oil change at 48,000 miles. I would like to change over to a synthetic oil. Also, I want to change transmission, transfer case and front & rear differential fluids.

The D is currently a daily driver for my wife. Occasionally pulls a 2000# boat or 2500# pop-up. And future plans are for it to eventually become my daily driver, hunting, fishing, working, you name it vehicle. Now, when I get a vehicle, I keep it for quite a few years and miles (my current vehicle is an 87 Ramcharger with well over 100,000 miles.)

So armed with the above information, what does everyone recommend?

 

[rockadaous]

I run royal purple in my engine & differential ....
mopar atf+4 in the tranny, transfer case and power steering

 

[Almond Pale Ale]

For the Tranny, power steering and T-case - MOPAR ATF+4. For the Diffs, a good synthetic 75W-90 (such as Mobil 1, Royal Purple, Amsoil or Redline). For motor oil, a good synthetic again (such as Mobil 1, Royal Purple, Amsoil or Redline). I started Mobil 1 in my '99 at 43k miles.

 

[durangokid98]

I just changed my T-Case fluid and my Diff fluids. Did 80w-90 for the diffs and AAMCO ATF 3 (which says on the bottle for cyrsler vehicles). For a good synthetic motor oil definitly go with Mobil 1. I just switched over as well.

 

[macfights]

for oil...the only way for me is amsoil

 

[Bamboo]

Red Line in the engine and pumpkins, ATF+4 in the transmission and transfer case. I made the synthetic change at 43,000 miles and have not regretted it. The engine oil gets changed at 7,500 mile intervals based on oil analysis test results.

Now I even use Red Line in my lawnmower.......

 

[Almond Pale Ale]

I just changed my T-Case fluid and my Diff fluids. Did 80w-90 for the diffs and AAMCO ATF 3 (which says on the bottle for cyrsler vehicles). For a good synthetic motor oil definitly go with Mobil 1. I just switched over as well.

I've used AAMCO ATF+3 and Quaker State ATF+3 but after using the ATF+4, I won't ever go back. The +4 is a better fluid if you're looking for a synthetic improvement.

 

[Saint]

In the engine and diffs I use Amsoil, for the tranny, and t-case I use ATF+4

 

[Almond Pale Ale]

Now I even use Red Line in my lawnmower.......

My Briggs and Stratton takes Mobil 1! Might as well use good oil if you're going to be keeping the equipment for a long time.

 

[dodgefan360]

I use base oils (non-synthetic) in my R/T. I change them too often to warrant use of any syn. fluid. After 2800 miles the oil is still brown. I change it every 2500 normally without fail, unless I get detoured from road construction on longer trips. I carry a full, heavy load at least once every week (store confectionary). I commute 8 miles one way to work. I'm also on an extended warranty for another 32K yet.

I run Quaker State 4x4 syn. blend in my lawn equipment. Two stroke I use QS 2 cyc. oil only.

 

[Amanc96]

I've just now switchover to amsoil. I had regular oil and hit about 14 mpg, i switched to Mobil 1 and averaged 13 mpg, and switched to amsoil and now averaging about 15 mpg. I did do an engine flush with amsoil stuff after the mobil 1 oil, so that might have something to do with the mpg increase.

 

[Hercules]

If you tow, I recommend going to a 75/140W oil in the rear as opposed to a 75/90w. The rear end gets quite hot....the 140w will give you added protection.

 

[Esh]

Currently for Motor Oil I'm using Castrol Syntec. Ran it in my old Saturn and am now running it in the D, never had any problems. My dad used to be an avid user of other oils, then I got him to run the base Castrol in his Dakota once, he hasn't wanted anything but Castrol since.

I've been debating on using Amsoil or Red Line, haven't decided yet, the Castrol Syntec works perfectly for me so far. Last time I checked, I had 6k miles on the oil, hasn't leaked or burned, and is still good according to tests. I would normally be changing it in the 4500-5000 range, but I decided as long as it is good, leave it in for a little bit longer.

 

[JoMc67]

Hello D Owners,
Soon im going to the dealership and getting the Tranny, Diffs, T-Case, serviced. Going to purchase Amsoil for the front and rear Diffs, how much fluid does each Diff need. I will let the dealership use their B&G ATF+ for the Tranny. I also need some good suggestions on aftermarket rear Diff covers and Tranny pans and let the dealer install them at same time.
Thanx
Joe

 

[Esh]

Check your Manual, it covers all fluid capacities.