Eric @ DMS

I've always been a fan of Mobil 1. Have I noticed any gains. No. As was said by others above, I use it for the peace of mind.

Now Royal Purple...hehe...sweet oil. Although not as easy to get as Mobil 1.

Airborneflyguy

Peace of mind is a beautiful thing aint it...I put synthetic (mobile1) after 500 miles. Ofcourse I had to garage the car and it sits for two weeks at a time so I just figured it'd make those periodic starts a lil less hard on her. Either way, if it helps ya sleep soundly at night I say do it.

PURESILVER05

I have a good friend who works at a dealership and he recommends waiting to around 10k before switching to synth. This is due to the extremly close tolerances and sharp edges within the engine.

ristuccia

someone eariler was asking about different weights. i think 5w20 is what the owners manual calls for but, for example, i use amsoils 0w30 in my f-150 thats normally 5w20. if you have a reason for using a certain viscosity lets hear about it, thanks.

05stangawsomecar

I would like to see the dyno sheet on that!

louder

I don't really know for sure if there is a horsepower increase or not but the engine sounds, and feels smoother. I went syn with twenty five hundred miles on my 05 gt vert. I used Valvoline 5w30, WallyMart had a good deal on it and I don't really know how it stacks up to Mobil 1 but it feels real fine.
One thing that I found odd was that up here in Canada, the GT's are sold with dino oil but in the good ole' US of A, they are sold with a syn blend. Does anybody know what's up with that?
(I did use a Ford filter)

Turbo 05

Go with Mobil1 Amsoil is an internet fad(always talked about on the internet but never in person), Mobil1 is proven and most highly modded cars that I have run into use it

DAVE05GT

Just did another with Mobile 1 and a K&N filter. I think it's a good combo and I'll stick with it.

05sonic_bluGT

"amsoil is an internet fad"... ????!!!! i drive a sprint car and the guy that builds these extremely bad a$$ engines calls me one day and says... "stop by here on the way home... you gotta see this..." he ran a $3000 305 chevy on methanol with some good heads and good guts on valvoline 5w30 fully synth. and it went 397.3... he drained it... added Amsoil 0w30 and fired it back up... the results? 418.1... in front of my very own two eyes... he later called me and says that he tried the same thing on a world of outlaws engine...(which is a 410 that is worked to the max... were talkin 60 grand for one of these engines...) and he says that he saw 17hp from that... im not gonna quote numbers cause i didnt see that one... but i can tell you that i am an amsoil dealer now and check out HOT ROD mag... a few months ago... i dont remember exactly what issue but THEY even said that they found 11 hp and 13 ftlbs by switching to amsoil... PUT THAT IN YOUR PIPE AND SMOKE IT!!! oh yea... ANYBODY THAT WANTS AMSOIL- CONTACT ME BY PM AND WE WILL TALK... IF YOU CANT GET IT IN YOUR HOME TOWN I CAN LOWER THE PRICE TO COVER SHIPPING AND GET IT TO YOU!!!