Thinking of running the 15W-40 and was wondering if anyone is running it and are they using oil analysis? How many miles are you usually getting out of a oil change,etc.... Any info would greatly help me out in making up my mind. Thanks in advance !! Ronny Clark

Ronny, any MAJOR brand 15w-40 diesel oil will work just fine in your truck. I've used Rotella in various trucks for well over one million miles. I'm currently using Mobile 1300 Super in my MAX. I change my oil out every 5000 miles (or close to it). Many on this forum elect to use synthetic motor oil. I'll not argue the point that under EXTREME conditions and/or truely extended oil changes synthetic may be superior to dino. However, I'll continue to use Mobile 1300 Super in my MAX.----------------------------http://www.dieselplace.com/forum/smileys/Cool.gif-----Phil

clarkrj





I have a lot of customers on the 15W-40 and this is what they do. In order of popularity.


1. Run 15K miles and change flter only at 7.5K and top off.


2. Run 10K and change oil and filter.


3. By-pass system and use oil analysis every 10K.


It is really up to you and what you can live with. Its hard for many to go over 5K miles and I do have some doing that as well.


I would choose number 1 or 2 myself if you plan on trading the truck after a few years. If you are going to drive it till the wheels fall off then go with a by-pass system and oil analysis.





Greg





Greg

I have run the Amsoil 15-40. It is a great oil. I ran mine for 10K with a filter change @ 5K. Changed and ran analysis....everything came back great. TBN, soot and viscocity looked great. That was with Hot Juice so its a little more extreme than stock.


15-40 is a good oil, I tried the 5-30 for the winter months (it gets damn cold here) and the viscocity broke down in 10K so I wouldn't recommend that but the 15-40 is good stuff.


I now run the Delvac 5-40. I changed because I buy in larger lots and I can use it for every season, no analysis yet, getting ready to change and sample in April.





Amsoil 15-40 good for at least 10K.

403turbo, I would like to ask what you are meaning as to viscosity breakdown with Amsoil 5w-30. How did you determine there was a breakdown in viscosity? Oil analysis or what?


I'm also an Amsoil dealer, but not as heavy into it as Greg. When I got ready to replace the oem oil in my dmax, I called Amsoil's technical assistance dept that is available to dealers.


I explained to the tech rep that the majority of my driving would be 2-5 mile trips around town here in griffin ga and that I would also be on an occassional long run at high speeds and loads with my 25' TT.


He said there was no question that the 5w-30 would be better for my around town, short trip use. He reccomended that I try the 5w-30 and see if I had any problem with excessive oil consumption or low oil pressure at idle, if so then go to 15w-40.


So I installed the Amsoil dual remote filter setup which uses a full flow filter more than twice the oem size and an even larger by pass filter. I now have 7000 miles on that setup and oil. This includes an extended 26 day camping trip that covered 3500 miles, partly in the Appalachian Mtns, and partly high speed interstate at speeds to 80mph pulling that 25' TT!


The oil level is still above the add mark and I have added none. I plan to get oil analysis at 10k. BTW, the hot idle oil pressure is approx 25 psi. And the bypass filter is keeping the oil pretty much soot free.

I'll second most of what landuytg said. I modify it by running the amsoil for 10,000 and change the filter every 5000. Greg has good prices and I order from him.

D.O.M.


Yeah, I got the viscocity numbers from oil analysis. The only issue with that sample was the viscocity. It got a little out of the acceptable range for 5-30 and given that its already pretty light I got nervous. The 5-30 perfromed well from an additive package standpoint. TBN was still very good, soot was minimal and wear metals were very typical for this motor. I just didn't want to run it in the warmer months given that the viscocity faded. Running two weights of oil was a PITA because I only change twice a year and I had to wait a year to use the leftovers from the previous winter.


So I went with the Delvac 1. Basically the same price and I figured I could run it year round. We will see, as soon as it warms up a touch I will be changing and sampling.

People seem to forget that 5W-40 is still a 40 weight and the same goes for the 5W-30. Winter time use in very cold climates the 5W-30 will aid in a much easier start plus the oil will be pumping to the vitals much quicker. A 40 weight when it gets real cold pumps slow and takes longer to get through the engine. I would still use the 5W-30 in the winter and the 15W-40 in the summer if I lived in a climate that got really hot.





Greg

Thanks guys!! Really appreciate all the info.