[JetmechF16]

I run RP 5w-20 in the cobra (I buy it at our BX for $6/quart). The blazer gets cheap pennzoil.

[12second5.0]

I had 230k on my 96 bronco when I sold it. All it got was the cheap bulk oil from work. Never even had the valve covers off.All I did was change the oil every 3,000 miles......

[blk01gt]

i use mobil 1 b/c synthetics have a stronger sheer factor

[T5killa]

Well Southwest Research that is here in San Antonio actually does testing on lubricants such as motor oils. When I was eating lunch with my dad there one day a guy from that division explained the differences to me. He said imagine the oil as little balls. Synthetics would be all the same size balls ( golf balls) and conventional would be all types of different balls ( football, basketballs, baseballs etc). He said in field testing in Iraw that tanks that run conventional need the engine rebuilt every 6000 miles. But the ones running synthetic only every 15k. But when tested in real world conditions are almost identical.

[BlackSunshine01]

one of the south west guys came to oreillys when i worked there and also said that there were pretty good temp drops when they switched the test equip with the rp as well. they said it was like 10 deg in the trans and like 8 in a rear diff.

[Nihil_2005]

I used Royal Purple then I decided to go with Amsoil. My car runs better with Amsoil and I will never go back with Royal Purple.