Scream

iTrader: (6)

I run Royal Pruple in my truck and love it!

Tom@SpeedInc

iTrader: (5)

I purchase AMSoil through Murrys auto a local chain around here, AMSoil claims to have long drain intervals like 15,000 or more miles I think. But I wouldn't go beyond 5,000 myself. The mobile 1 oil i've just become intersted in is their 0w-40 it is a German spec oil that is used as a factory fill for BMW, Mercedes etc.

TIM02Z71

The oil drop web site is great. The only problem is no-one seems to totally agree on anything and you don't know who is right or wrong.

408 Stepside 01

One of my college professors had said that oils chemical make up changes after about 3000 miles and one of the key factors about synthetic is its molicules are tighter; meaning that it can with stand more abuse and longevity. But on the other hand not all motors should use synthetic, depending on the tolerances etc.

BigJ

Royal Purple 5W30 since the truck had 5,000 miles. I now have 60,000 miles and have not had any issues. This is good stuff, if I ever switch, it will be to Redline, but so far, I'm sold on R.P.

JWRENCH

Yeah TIM02Z71, I know what you mean about everyone having a different opinion over at the oil drop website.

I pretty much just keep up with the used oil analysis the people post and decide for myself.

A few things I've learned are that for a synthetic Mobile 1 always runs a little thinner than most. Also Amsoil is only good for around 12,000 miles not 25,000 as they claim. And changing from synthetic to dino is fine but changing a higher milage engine to synthetic from dino will cause the seals to start leaking cause it'll clean out all the built up funk in there.

TIM02Z71

All that makes sense about not using synthetic on an old motor. Does anyone know the prices of Amsoil, what grades are recommended for what type of driving and engine displacement? Thanks for all the info guys.

Tom@SpeedInc

iTrader: (5)

I purchased AMSoil for $6.99 a quart, and I use 5W30 as the manufacture advises. AMSoil I belive is a Group iV base synthetic, ester base I belive. It is a real synthetic oil. Mobil 1 is the only real synthetic oil easily available to the public it is a Group V base unlike Castrol, Pennzoil, Quaker state and any other "claiming" full synthetic and sythetic blends which are actually Group IIIs and are just mineral oils that have been modified with anti wear anti oxidising etc additives and make the molecules tighter. The best cheap dino oil is Chevron/Havoline they are a group II and surpass other off the shelf dino oils that are group I that in some cases are more expensive. The information I have has been complied from the oil drop and links from that site.