I recently had a conversation with a close friend of mine who has a brother who is a diesel mechanic for the military. His brother told him that he puts 1 quart of 5w30 in his fuel tank for every 15 gallons of fuel. He claims that this is making his truck run cooler and gives him an extra 100 miles to the tank. Is this really possible? Is this a good idea? I immediately see red flags, but I have been reading a lot on the net about diesel being an oil-based fuel to begin with; and with all this new bio-diesel coming from vegetable oil, etc. I have started to think there might be some truth to this. Has anyone ever heard of this?

Use the search button!!!!

Use the search button!!!!


He's new, give him a break.

Welcome to the site, there is a lot of info here to answer your questions. 100 miles to a tank, not a chance. The only thing it really helps with is lubrication. Some guys do it to get rid of used oil. It has to be filtered VERY well, and don't go overboard with amounts. I've heard reports of 1-2 qts per tank in newer trucks is safe. USLD doesn't lube like the old diesel, so some type of lubrication additive is recommended. There's a certain type of 2cy oil guys here use. I don't know too much about it, but please don't think it's some miracle MPG juice b/c it's not.

Read through this forum, you'll find something:

http://www.dieselplace.com/forum/forumdisplay.php?f=64

Sorry for asking such a repetative quesition. I am indeed a newbie to this site. The search button did indeed bring back a bunch of discussion on the topic. Sounds like the jury is still out as to what should be used as the best, safest, most cost-effective lubricant. I'm glad that this information has been discussed as I had never heard of this before, and the last thing I was going to do was put anything in my truck that might cause it harm. A few bucks at the pump aint worth thousands in damages.

i have been using 2 cycle oil in my diesel for over 4 years with excellent results. i buy the cheap wal-mart supertech oil in a quart and split it in 4ths over 4 tanks.

Whats this "A few bucks at the pump" all about?

i have been using 2 cycle oil in my diesel for over 4 years with excellent results. i buy the cheap wal-mart supertech oil in a quart and split it in 4ths over 4 tanks.

x2! Except I started last fall. It really quieted down my truck. It runs smoother too.

I just started useing 2 cycle oil from walmart also (the cheap stuff). So far I have not had a problem and it does seem to run alittle smoother.

Check around guys on price. I found a synthetic TCW-3 2 cycle mix oil (same as wal-mart) for $2.20 a quart. I half it per fill up. It is not a brand name, but meets the exact same standards as the wal-mart stuff according to the bottle. I just started using and went two tank fulls without any and my throttle surge came back. First tank back with the pre-mix and no idle surge.

P.S. it is at O'Riely.....

Jim

I think he is pulling your leg with the 5w-30. I run mostly waste jet A and run a quart of two stroke per tank to make up for the lack of lube. I have a bunch of miles on the clock over the last two trucks i have owned and had 0 issues.