I HAVE BEEN RUNNING 20W 50 OIL IN MY 300,500 MILE JEEP 4.0. THE 4.0 HAS BLOW BY AND SLUDGE.THE 20W 50 HELPS (A LITTLE ) WITH NOISE.CAN I RUN THIS OIL OR SHOULD I GO BACK TO 5W 30
I would not use 20W-50 in the winter unless you live in a warm climate. I believe it's suggested that you stick with the manufacturer's recommended oil weight while doing a ARX treatment.
-- Edited by TurboJim on Sunday 6th of December 2009 12:06:20 PM
I have been using 20w 50 for about a year ,winter and summer with no problems ,but i did see where they did recommend stock oil for the treatment, thats why I was asking
Use the oil viscosity your engine calls for. While Auto-Rx does not care what viscosity you use, it makes good sense to stick with standards when cleaning out a dirty or sludged up engine.
The same engine has spec'd everything from 5w-20 in Arctic conditions to 20w-50 ..but that was in the 70's some time. It works ..but it's surely not required.
I'd probably go to a 15w-40 as top visc. for the treatment. I'd say go to a 10w-30, but a 15w-40 diesel oil should function in most climates with a 4.0 My son ran it in the low teens here a few winters ago. The engine didn't seem to notice at all.
He drives 40 miles one way to work, so at least 80 miles per day, mostly interstate I believe. I would like to see him use a conventional 10W-40 or 15W-40, at least during the winter months. We often see winter night lows in the 30's and some in the 20's here in upstate SC. Once or twice a year it might get in the teens.
