Yes they filled it up wit 87 mobil?? I am noticing after the seafoam that it runs much smoother and has improved in throttle responce.But still has some bugs to work out...but overall it was worth the effort .....That $5 can of seafoam worked wonders..................................

 

What's the deal with this Seafoam stuff anyway? Where can it be purchased? I just flashed my computer when I installed my intake and exhaust and it did take awhile for the performance to come back. It does'nt sound like this is your problem though. I think carbon buildup may be the culprit here.

 

If you ever have problems with a "STEALERSHIP" call GM Customer Care. When my motor blew cause it soposedly had "piston slap" (yah, bullshit it did) the dealer i went to didnt want to do a ****** thing for me. They said cause i had a cold air intake ( that was the only mod except a Flowmaster) thats what caused me to throw 2 rods. I called GM Customer Care and they took care of everything. GM even told them to get my truck done in 1 week. And it was done in 1 week.

 

You can buy seafoam at any napa auto stores..$5 a can ..I put some in the oil -gas and through brake boost hose and it worked great..Follow instructions..............................Its Great stuff.