MDS Hemi Fuel Type's
 

I bought a new Chrysler Aspen with the 5.7L a couple of days ago, andI don'tknow which grade of fuel to fill up the Aspen's tank, regular or premium?I asked a car salesman at the dealer but they said just fill it up with regular and do premium every three times you fill it, and another friend with a C5 vette (also a 5.7L) said to do premium fuel all the time to prevent engine knocking? So tell me which do you use and what would you recommend for the Aspen?

RE: MDS Hemi Fuel Type's
 

it will say in the owners manual on what type of fuel to use

RE: MDS Hemi Fuel Type's
 

Yea I forgot to say that the dealershipI bought it from didn't get owners manualsfor the lastfive Aspen's they sold. So that is why i'm asking.

RE: MDS Hemi Fuel Type's
 

get them to get on out of another aspen

RE: MDS Hemi Fuel Type's
 

I bought the last one the dealer had. You can't just answer my question?

RE: MDS Hemi Fuel Type's
 

if i had that info i would we dont have an aspen on the lot right now so i cant get my hands on a manual. I just saw in another post with a 5.7 hemi 300 they said the mfg rating of fuel was 89 so I would say mid grade in your aspen.

RE: MDS Hemi Fuel Type's
 

According to the manual you should use 89. You can go to http://www.chrysler.com/owners/manuals.html#, and download the owners manual, and keep it on the computer. Did the dealer order you one?

RE: MDS Hemi Fuel Type's
 

Yes the dealer did order one and apparently they are backorderedon all the Aspen manuals so I won’t get it for another month or so.

FWIW, I've used regular gas (2007 5.7) for decades and never had a knock even when pulling a loaded U-Haul through the Colorado mountains. I have also tested premium and my MPG was about the same - MPG gain not worth the higher fuel cost..