$600.00 for an EGR? It is no wonder to me that the same people overcharging you for a 1 Hr labor job (having done it myself) are the same who say it is ok to put 87 in the vehicle that specifically "reccommends" nothing lower then 89. They want your buisness! Using 87 will cause problems to your truck, which means more of your $$$ goes into their pocket. No exactly building rockets here-

Picks and shovels. Who do you think made more money, those digging for gold, or the ones who sold the picks and shovels?

 

I've had my 07 1500 with the 5.7L for about a week now and have been running 87 because that's all I've ever run in any vehicle I've owned. I just got rid of a 04 Ford Escape and it got about 21 combined mpg. I'm on my second tank with the Ram and I'm averaging about 18.5 combined mpg. After reading this thread, I'm switching to 89 octane or better. I even read the owner's manual which stated that 89 is recommended but 87 can be used, I still ran 87 octane and have noticed a little hesitation on starts. Can't wait to get my CAI and Superchips Vivid Linq and see what this hog can do.

 

I haven't read all the pages of this post but I can tell you the best answer to avoid any engine problems. Get a SuperChips and run the performance tune. Done. That's what I do and I in no way have that much money but it's better for me to run better gas and pay a little more at the pump than pay ridiculous amounts in repairs. 93 down here is only like 20-30 more cents then 87

 

89 on stock tune is fine, any higher octane will not benefit you, but I wouldn't run 87 unless I specifically was running a tune that retarded timing and specifically said it was for 87 octane. Seems everybody who has had a cylinder go boom was running 87 in a Hemi for an extended period.
Obviously, if you have a tune that calls for higher, then you need to run higher...

 

No way in heck I'll run 91. I'll stick with 89

 

Running a higher octane won't hurt anything, it's just not going to give you any benefit with the stock tune over running 89 octane. Now running TOO LOW an octane fuel is a recipe for trouble...

 

Nothing but 93oct here. I am running a 91oct tune, but always ran 93oct. It has additional cleaners which most people dont even know about, so your getting more for your money.
With all the money some guys put into these trucks with mods. Useless mods as well. I cant believe how many cry about $.10 more for 89 over 87oct. For a full tank, your talking about $2.40. C'mon guys. You spend crazy amount of money for Royal Purple...etc and you dont wanna drop an extra $2.40 for secure safety of your engine. Ridiculous.
At 12kmi per year getting 15mpg, that's 33 fill-ups. 33X$2.40 =$80 extra per year. Makes ya sound pretty cheap doesn't it?
USE 89 OCTANE at the minimum ESPECIALLY with al this 10% Ethanol added crap!!! It'll keep your engine cleaner and running stronger PERIOD!

 

Your assumption is valid, but here in Jersey, 89 averages $.35 and 93 sometimes better than $.50 more a gallon. Wish it was only 10 cents. Remember the good old days when the difference between regular and premium was only 4 cents. But then again, those nylon tires were only good for 20K and just did not stop on command. Sorry for the rant, but I'm getting old and it ain't pretty.

 

Wow, in my area 89 octane is either 15 or 20 cents higher than 87 octane and premium will run between 25 & 30 cents higher than 87.

I just filled up with 93 octane (SC Performance Tune) after work this evening because I'm heading up to the farm in Georgia straight from work tomorrow for my 4 day weekend. Paid $3.32 for 93 octane E10 and yup, added 2 oz of Star Tron to it...

 

here in Ontario 89 is usually 5 cent/liter more than 87 and and the 91 is usually 10 cents/liter more. this usually ads up to about $5-10 per tank. in my opinion it is worth it. up here the 91 octane gas is ethanol free. i think i have read ethanol in raises the octane rating so the gas company can give crappier gas but in the end it still has the same octane rating.