Racerx250: My 01 PSD has 265K miles on him. I bought it from my wifes company she works for. Used as a shop truck, for 3yrs. Almost all the 263K miles were highway miles running oil field parts across the country. I dought they changed the oil every 5k miles. Everyone I asked didn't know or didn't care. Mostly Rotella 15W-40 was used. The truck went through 3 sets of injectors during the first few yrs. I bought the truck after the last set was installed. After taking off the Valve covers on both sides, and looking down into the heads. I found alot of nasty sludge. I cleaned out all that I could, and installed the valve covers back. I talked to a fella in our Oklahoma Powerstroke Club, he told me about Auto-Rx.com. After doing a bit a research and talking to Frank. I went through 2 cleaning phases of Auto-Rx and Delo 400 15W-40. After the cleaning phases, I switched to a mix of 2gals of Mobil Delvac 15W-40 & 1gal and 2 qts of M1 TDT 5W-40 synthetic, for the last 2 months. Just the other day my harness under the valve cover came loose. Took it to my mechanic to have him replace both sides. He called me, and asked me what kind of oil I using!!! I told him about the Auto-Rx and the Mobil switch. He said the inside of the valve covers looked like almost new. Yes a bit of tarnish still remained but no form of sludge remained. He was very impressed.
During the cleaning phases: I replaced the oil filter every 1k miles. Didn't want to take the chance of the filter clogging up, due to I didn't know just how much goo was in the oil pan and through out the motor.
Granted: I didn't notice any form of engine noise decrease till after the 2nd cleaning phase. Then really noticed a difference after I poured in the Mobil Mix. I'm sure any synthetic will do the same-->{5W-40}.
I didn't want to run a straight 5W-40 synthetic until i knew the motor was as clean as I could get it. I had a timing chain cover leak before the cleaning phases. The Auto-Rx cleaned and swelled the seals I assume, and stopped the small leak.
The 7.3L now runs very smooth and quite abit quieter then before. As for now the M1 mix has 3k miles within it and still showing full on the dipstick. The
Now I'm looking at running either M1 5W-40 or Rotella 5W-40 yr round. After I install a by-pass filter system and find a good OCI with a few UOA's. Hopefully 10K to 15K miles between oil changes. Time will tell.
Even though some call Rotella 5W-40 a fake synthetic, I feel it's a darn good oil. Many UOAs have proven it to be a top performer.
Before U switch-->Check out Auto-rx. Frank has alot of info on his site.
Yes-amsoil 15W-40 will work great. Since you live in a cold area, ya might think about 5W-40 yr round. You will get better cold start ups and less wear on that motor. If ya chose to use Amsoil or M1 which are true PAO synthetics, I would think about installing a By-Pass filter system to take advantage of the Extended Drains. This is all JMHO. Good Luck.
During the cleaning phases: I replaced the oil filter every 1k miles. Didn't want to take the chance of the filter clogging up, due to I didn't know just how much goo was in the oil pan and through out the motor.
Granted: I didn't notice any form of engine noise decrease till after the 2nd cleaning phase. Then really noticed a difference after I poured in the Mobil Mix. I'm sure any synthetic will do the same-->{5W-40}.
I didn't want to run a straight 5W-40 synthetic until i knew the motor was as clean as I could get it. I had a timing chain cover leak before the cleaning phases. The Auto-Rx cleaned and swelled the seals I assume, and stopped the small leak.
The 7.3L now runs very smooth and quite abit quieter then before. As for now the M1 mix has 3k miles within it and still showing full on the dipstick. The
Now I'm looking at running either M1 5W-40 or Rotella 5W-40 yr round. After I install a by-pass filter system and find a good OCI with a few UOA's. Hopefully 10K to 15K miles between oil changes. Time will tell.
Even though some call Rotella 5W-40 a fake synthetic, I feel it's a darn good oil. Many UOAs have proven it to be a top performer.
Before U switch-->Check out Auto-rx. Frank has alot of info on his site.
Yes-amsoil 15W-40 will work great. Since you live in a cold area, ya might think about 5W-40 yr round. You will get better cold start ups and less wear on that motor. If ya chose to use Amsoil or M1 which are true PAO synthetics, I would think about installing a By-Pass filter system to take advantage of the Extended Drains. This is all JMHO. Good Luck.
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