98Dak,

It's not a differential, it does not have "hypoid" gears. It's not 75w-90 or 75w-140, it's Manual Transmission Fluid or "syncromesh."

Don't use gear oil, the NV3500 is NOT designed for it. Syncromesh fluid is lighter and won't wreck the synchronizers. Yes, some transmissions do take gear oil, but not the NV3500.

 

Sweet thanks for your help guys. I don't think the temp was in question, just if it is the right oil or not. Thanks again!

 

Mobile 1 is both trans oil and Diff oil look what your manual says 75 - 90 as far as I know your gears are in your trans? yes and your Diff.

Just go with your manual what it says

 

go with what the manual says thats all I will say call Mobile and ask them

1-800-ASK-MOBIL to be sure they will know

 

look it up here also for redline oil

http://www.redlineoil.com/application.aspx

 

98, thanks for the link.

Try this, put in 2000 Dakota 4.7 Sport NV3500 - that's mine. It does NOT suggest you use the same fluid as in your differential. It uses 70w-80 GL-4 gear oil for the transmission, and 75w-90 GL-5 gear oil for the differential.

On the GL-4 gear oil it says "Safe for brass synchros, as it lacks the reactive sulfurs found in most GL-5 oils that cause damage."

On the GL-5 gear oil it says "This product is not designed for use in most manual transmissions or transaxles in passenger vehicles, since the extreme slipperiness may cause synchronizer mesh issues that lead to shifting problems."

Mobil 1 gear oil says "Mobil 1 Synthetic Gear Lubricant LS 75W-90 is SUITABLE for use in modern high performance automobiles like SUV's, Vans and Light duty trucks requiring API GL-5 level performance."

It's fine for the differential, I use it there, it's not for a manual transmission.

 

All I can say is I have the Mobile 1 75W - 90 in my 1998 5 speed manual truck for 4 years with no problems ever my reverse sucks but it always sucked before the Mobile 1 I was hopeful the Mobile 1 would fix that irritation but from what I have been told that’s a common problem with that trans well my truck has always been a bear getting into reverse frustrating

No biggy just trying to get good info.

But Im a bit confused my understanding is that the 1997 to 2004 trucks were all the same with small changes but it showes the 2004 trans as a different trans than the Nv3500 so maybe Im wrong on the trans oil needed.

 

No worries 98. There are lots of little differences between the years, especially '00 - '01.

DDC is an NV3500. That's the order code.

 

Maybe I’m lucky I switched to the Mobile 1 75W 90 as I moved to HOT HOT Arizona but if I lived some place cooler it may of caused me problems only thing I didn’t like was the smell I noticed on very hot days you could smell that trans oil coming up the shifter I guess that Mobile 1 75W 90 is stinky stuff.

But I have used my Truck in California on a few cool days with no change in shifting.

I do believe I called the Mobile 1 help line on using that oil and they said its ok to use in my trans.

 

Hey guys, thanks for all the advice, I decided to roll with the penzoil syncromesh. Here's my filling rig, and check out how much metal was on the magnetic drain cap... 71K miles