[quote author=MAragorn link=board=20;threadid=13997;start=0#133682 date=1051737600]<br>I follow the 3750 mile rule for 3 reasons:<br><br>1. It is a good idea.<br><br>2. Nobody can second guess you and say that you were not doing what was necessary if there is a warranty problem.<br><br>3. Quaker State will extend the engine warranty to 250,000 miles if you stay below 4000 miles on your oil changes.<br><br>http://www.quakerstate.com/pages/pro...pplication.asp<br>[/quote]<br><br>I'll betcha Mr Quakerstate has so many loopholes in his 15 part &quot;warranty&quot; that if you sneezed while changing the oil that would void it. Just hype to get you to use an inferior product. Good products sell themselves.<br>Sure glad DC didn't rec'd 3500k oil changes all these second guess'rs would change it every 1000k then :

 

[quote author=Vaughn MacKenzie link=board=20;threadid=13997;start=0#133720 date=1051743216]
MAragorn,

As far as I know Quaker State doesn't make an oil that is acceptible to use in the Cummins. The oil needs at least a CH and preferably CI rating. I took a quick scan at their website and didn't see any of their oils that will fill the bill. They all say for gasoline and gasoline turbocharged engines.

Vaughn
[/quote]

Quaker State (why do I always spell it &quot;Quacker&quot; ) Universal HDX® Engine Oil is CI rated. Here's the cut sheet. http://www.pzlqs.com/Tech/Pdsheet/Qu...iversalHDX.pdf

Tom

 

<br>Commatoze &amp; MAragorn,<br><br>Quaker State does list a Synthetic Blend 15w-40 CH-4. Since this info was dated May 2002, it is now a year old. One would need to contact Quaker St. to determine if this has been upgraded to CI-4 to meet 2003 model standards.<br><br>(From<br>http://www.quakerstate.com/pages/techdata/index.asp)<br>For 4x4s, SUVs, and Trucks<br>DESCRIPTION<br>QUAKER STATE® SYNTHETIC BLEND MOTOR OIL for 4x4s, SUVs, and Trucks is specially formulated for these hard<br>working engines. Engines in 4x4s, SUVs, and trucks are put under stress from pulling or hauling heavy loads. This stress<br>can cause an increase in engine deposits or wear. QUAKER STATE® SYNTHETIC BLEND MOTOR OIL for 4x4s, SUVs,<br>and Trucks is formulated to protect these vehicles in such harsh driving environment.<br>FEATURES<br>QUAKER STATE® SYNTHETIC BLEND MOTOR OIL for 4x4s, SUVs, and Trucks exceeds:<br>• North American warranty requirements for U.S., European and Japanese vehicles with gasoline, gasoline turbo-charged,<br>and light-duty diesel engines where API SL, SJ, CF, CH-4. CG-4.or CF-4 (15W-40) oils are specified<br>• European ACEA A1-96 (SAE 10W-30) and A2-96 (10W-40) standards<br>• ILSAC GF-3 and Energy Conserving performance standards (5W-30 &amp; 10W-30)<br>• Passes Japanese valve train wear tests (5W-30, 10W-30 &amp; 10W-40)<br>• Mack EO-M Plus, Cummins 20076 (15W40)<br>BENEFITS<br>Compared to conventional oils, the results are:<br>• Improved resistance to thermal breakdown<br>• Lower oil oxidation<br>• A clean running and long lasting engine<br>• Meets Ford WSS-M2C171C (15W40)<br><br>May 2002<br><br>

 

I don't doubt that if there was a problem Quaker State will try to weasel out of it, but I am buying the oil in gallon containers and having Kwik Lube do the oil and filter change, attaching the receipts and having them note on their printout that the owner supplied the oil and the filter. Maybe a waste of time, but I am dang sure changing the oil often enough and getting the rest of the truck lubed often too. Seems like I never have a problem with U-joints or the front end of a vehicle if I keep it lubed enough.<br><br>Quaker State DOES have a diesel oil called HDX:<br><br>http://www.pzlqs.com/Tech/Pdsheet/Qu...iversalHDX.pdf<br><br>It is CH-4 and CI-4 and meets Cummins requirements, according to their info.<br><br>I buy it at Walmart for seems like around $5/gallon? Anyway, with me buying the oil at Walmart and the filter from Geno's, and with Kwik Lube doing all the work it runs me I think $42 per oil change.<br><br>I figured if I do this oil change every 3750 instead of 7500 miles, it will run me $1400 over 250,000 miles. May be a big waste of money, but I think it is probably going to keep me from ever asking Quaker State to replace anything anyway.

 

I looked so fast I missed the QS HDX <br><br>Vaughn