octane question for the 5.7 hemi

[djais1801]

The 2008 Aspen Limited AWD Hemi is my wifes truck...which has now become her company vehicle w/ miles and gas being reimbursed.

Here's the problem, the company said they only will reimburse gas for regular unleaded 87...and I know that the 5.7 requires minimum of 89.

What long term damage will occur using 87, and/or is there an additive I can use at each fill up to help prevent the pinging that occurs when lower octane is used?

Any advice is appreciated!

 

[5.7 hemi]

Actually the 5.7 takes 87 octane, the 6.1 uses 91 and the 3.5 uses 89 octane. I know this cause my 5.7 while not stock, is suppose to use the 87, but I run a tune in it so it gets 91 and my magnum call for 89 and the tune I have in it also calls for 89.

Just run the 87 in you wife's car and all will be well.

 

[Stumper]

My owners manual says to use "only" 89 octane for the 5.7L Hemi..?

 

[djais1801]

My owners manual says to use "only" 89 octane for the 5.7L Hemi..?

mine too

 

[fatecaptured]

I try to run 91 octane in my truck. Simply because it doesn't ping as much as 89. 87 isn't recommended by the manufacturer for a reason.

 

[5.7 hemi]

Hmmm! Maybe I got it wrong.....could have swore the rams require only 87.

 

[fatecaptured]

Not according to my owners manual. I'm sure with a tuning chip or device you could use it. But a few more cents a gallon seems cheaper to me. But that's just my dumb logic.

 

[Moparsmitty]

Have your wife explain to her company that her truck requires at least 89 octane gas and offer to pay the difference in the price. I would be very reluctant to use 87 octane in the truck on a long term basis. It probably wouldn't hurt the engine to use 87 octane in an emergency, but why take the chance of damaging your engine in the long run. I always use the recommended fuel specified by the owners manual. I figure that the factory engineers know a lot more about what any particular engine requires for fuel than I do, so I'm going with them.

 

[djais1801]

 

[5.7 hemi]

That says "recommended", in other words, towing, performance, etc. The 87 would be just fine for the better half's way of driving......unless your married to Danica, lol!