Oil Vicosity and idle romp

[Invader]

Iknow this is opening a whole can (and More) of worms but I'm going to ask anyways



I'm curious to know what grade/make of oil people are running in their PS.
The reason I ask is I have an 03 with the latest flash, have 45,000 miles on it and I'm ready for another oil change.

I've used AMSOIL, Royal Purple, Texaco Ursa, and Motorcraft 15w40.(all)
The RP ran like crap when it was cold. (idle romp).
Same with the MC but I only used that when the engine was new and they were still having Pilot injection issues as well.

I used the Motorcraft 10w30 for 3000 miles, and the last 1000 of it the MPG dropped by over 1 mpg.

Right now I've got the Amsoil 5w30 series3000 HDD but I think it might be on the light side. (Never any idle romp though)

anyone use a 10w40?

I'm using the synthetics because as I it might help with soot build up on the EGR system and maybe mileage.

Also What has been the best choice for your oil type to reduce the idle romp.?

 

[ktpauley]

I use Rotella T 5W-40 synthetic year round. I don't have the romps in the winter. Keith

 

[oi8228oi]

Rotella 15-40... your not supposed to run anything but 15-40 in a diesel motor.check your manuel.

 

[jharvey]

I've used Rotella T 15-40 in both my PSD's and never had a problem. As long as it's rated CI-4+ you should be okay.

 

[DaveBen]

The rating of the oil is as important as the weight. Use only CI-4 or CI-4+ rated oils. 30 weight oil is too light for the diesel engines.

Dave - 5W40 Rotella syn

 

[ktpauley]

This is right from the diesel supplement, and Ci or CI+ rated. Keith