1). I just purchased a 2004 GMC 2500HD Diesel. I was told by the dealer I can purchase a "chip" to give me additional HP.


Can you recommend a site for the chip.


2). I've been hearing allot about the AMSOIL products for my diesel. Any comments from the group.

Do a search for the performance mods....goobs of great info here. I have no experience with amsoil but it is a popular choice...search that one out too. Right now to my knowledge....your power options are from edge, bully dog, quadzillia, tts and BD right now. Did I forget any guys? Oh...enjoy your new truck!http://www.dieselplace.com/forum/smileys/smiley4.gif

joe- As previously stated, there are a bunch of options out there as far as chips go. I suggest you do a search on the different chips and you will have plenty of reading material for a while. If you have any questions or need some help, give me a holler.

Soon to have edge on my LLY, had it on my LB7. That the only way I will go.

Just remember - If you add the chip, don't tell the dealer. I'm surprised the dealer said that. Dealers vary but I would think the official line from GM is that you shouldn't do it if you want them to honor your warranty. If they make such a big deal about changing tires what do you think they would think about a chip. Just make sure that if you add it, you take it out before you go in for warranty service.

dont worry too much about the oil if thats what you are referring the amsoil to, just change it frequently - ive been doing some research on my own and have concluded that regular changes, about 3000-5000 miles with regular oil is just as good if not better than synthetic at longer intervals !! now tranny and diff is another subject, run the good stuff there !

Kind of a dumb question but i was told that the front and rear ends already have synthetic in them . Is that correct?http://www.dieselplace.com/forum/smileys/smiley3.gif

Well, the General has been a little cheap with the fluid levels.
My 4qt rear diff measured a hair over 2 qts when I drained it at 1000
miles on the odometer.



I drained mine and refilled it with 4qts of Mobil 1 synthetic.

FastToys,

I believe one of the techs (Eric?) posted a note a while back saying that GM made a switch to synthetic for the front during the middle of the 2004 model production run. The rear has used the synthetic "grape juice" gear oil for some time.

My truck was made in April of 2004. I have already changed out the fluid in the front and it had the same "grape juice" smell as the synthetic fuild in the rear. I am fairly sure it was synthetic. Edited by: BH in AZ

Is it prolly a good idea to go ahead and drain the front and rear diffs. and refill with new synthetic?? I have about 15,000 mi on it .