Rotella: The world's first ever combined hair oil, foot ointment, and salad dressing
CF Veteran
Joined: Jan 2014
Posts: 1,540
Likes: 351
From: District of Columbia
Year: 1998
Model: Cherokee (XJ)
Engine: 4.0
I just switched to T6 on my last oil change. I did notice a slight increase in mileage I have not noticed any oil leaks at all since the change. Right now i have 266,000 on my jeep. As far as I know it was always run on 10-30 conventional its whole life. I only started running Diesel oil in it after reading this right up Salad did. The only way to find out if it is going to leak with the change over is to change it and see. But if you did the o-rings and the cover gasket you should be in a good spot to change it.
Senior Member
Joined: Nov 2013
Posts: 616
Likes: 4
From: Vernon NJ
Year: 1998
Model: Cherokee
Engine: 4.0
I went from 15-40 Rotella T5 conventional to 5-40 T6 full synthetic. I noticed an increase in mileage. Oil synthetic circulates better in the engine and in turn uses less energy on the pump netting slightly better mileage. It only went up about 1 mpg.
Thread Starter
Herp Derp Jerp
Joined: Nov 2011
Posts: 18,251
Likes: 17
From: Parham, ON
Year: 1999
Model: Cherokee
Engine: 4.0L OBD-II
Probably see a slight drop going from 10w30 to 5w40 if you have a long commute. If you have a short one you may not notice a change, or see an increase, since you go from a 10W dino juice to 5W synthetic.
CF Veteran
Joined: Dec 2011
Posts: 1,777
Likes: 22
From: PA KOTUFU!
Year: 1998
Engine: 4.0L 162,000
OK, I used Rotella T6 in both my XJ and Taurus for the last 1 year.
Switched back to Mobil 1 5w30-
-'99 Taurus with 200k picked up 1.5-2mpg on my same usual 400 mile trip.
-'98 XJ with 160k picked up 1-1.5mpg with everyday average/mixed driving.
For what it is worth and I don't know what it means except that my mpg went up.
Switched back to Mobil 1 5w30-
-'99 Taurus with 200k picked up 1.5-2mpg on my same usual 400 mile trip.
-'98 XJ with 160k picked up 1-1.5mpg with everyday average/mixed driving.
For what it is worth and I don't know what it means except that my mpg went up.
CF Veteran
Joined: Oct 2013
Posts: 1,589
Likes: 2
From: Denver
Year: 99
Model: Cherokee
Engine: 4.0
Going to start using some kind of Rotella soon. Supposedly have a rebuilt Ford 5.8L in the van I just got. Might run a 0W30 or something similar though, as it'll be a ski shack and I want it to crank over easy up in the mountains.
CF Veteran
Joined: Jan 2015
Posts: 1,508
Likes: 5
From: Oregon Coast
Year: 1999
Model: Cherokee
Engine: 4.0L I6
CF Veteran
Joined: Sep 2010
Posts: 12,692
Likes: 6
From: Mercer County, NJ
Year: 2001
Model: Cherokee
Engine: 4.0L I6 HO
When o was reading up on it, that's exactly what I heard but most articles are a few years old. I was curious. I saw someone with a Mazda did a UOA of supertech and the number were good.
CF Veteran
Joined: Jan 2015
Posts: 1,508
Likes: 5
From: Oregon Coast
Year: 1999
Model: Cherokee
Engine: 4.0L I6
I not willing to take the risks. I will stick with my UOA proven delo 400. I would be happy to post the analysis report if anyone is curious.
CF Veteran
Joined: Sep 2010
Posts: 12,692
Likes: 6
From: Mercer County, NJ
Year: 2001
Model: Cherokee
Engine: 4.0L I6 HO
CF Veteran
Joined: Sep 2010
Posts: 12,692
Likes: 6
From: Mercer County, NJ
Year: 2001
Model: Cherokee
Engine: 4.0L I6 HO
CF Veteran
Joined: Jan 2015
Posts: 1,508
Likes: 5
From: Oregon Coast
Year: 1999
Model: Cherokee
Engine: 4.0L I6
CF Veteran
Joined: Jan 2015
Posts: 1,508
Likes: 5
From: Oregon Coast
Year: 1999
Model: Cherokee
Engine: 4.0L I6