Rocky Mountains Ram owners...what octane gas do you use?

[Crockett]

Our manual recommends using 89 octane In the Ram; however, when you get in the higher elevations, 87 becomes the new 89. What do you run in your truck if you live in a high elevation state? I was just in Colorado, and it was pricey running high test while there Just to keep in line with manual recommendations. I’m on the east coast, so 89 is everywhere, but it doesn’t exist most places out West. So, what is the common practice for trucks in higher elevations.

 

[Boston]

The lower air density is your guide.

Because the air is less dense, less air flows to your car's engine. This translates to a slightly richer air-fuel ratio, and deters engine knock. For that reason, you'll find that regular gas carries an 85 octane rating here in Denver and throughout Colorado, Wyoming, Utah and Montana.

 

[ColoradoCub]

I live in the springs, 100% of my driving is done between 6000-11000 ft. I switch back and forth between 85-87. Never had an issue and my fuel mileage is the same , unloaded or towing

 

[WasatchBack]

7-9k feet in Utah, 85 works fine

 

[hoopmanut]

I use 87 here in Utah.

 

[MileHi Guy]

This is an older thread but, I am in Colorado… I used 88 octane last weekend for a trip up to the Mountains. I got 21 mpg on the trip, about 400 miles. I’m wondering if I could’ve gotten away with a lower octane gas since I was at altitude (sometimes over 12,000 feet above sea level). I’ll probably go with a lower octane on the next fill up and see how that goes.

 

[Kaderast]

I live at 7,000' in CO and have always been using 85. Doesn't seem to be a problem at all.

 

[MileHi Guy]

I live at 7,000' in CO and have always been using 85. Doesn't seem to be a problem at all.

Good to know. Thanks for the post. Have you towed at all? Had any issues with that at altitude with 85?

 

[Kaderast]

Good to know. Thanks for the post. Have you towed at all? Had any issues with that at altitude with 85?

Only 4,000 miles on the truck, haven't done any towing yet. Generally most of what I tow is a snowmobile trailer in 4wd in the winter, so expecting mileage to be horrible regardless. My last few tanks of 85 octane, mixed driving, has been in the 18-20mpg range. Just put in 91 octane this morning on a whim....will see if I notice any difference (doubtful).

 

[IvoryHemi]

When I was towing 7k through Colorado I stayed with 87. I didn’t want a tank of 85 heading back to the flatlands