Ok everyone, names Jim, I drive a 07 Rubi with a RE 3 1/2" lift on 35 12.50 Super Swamper SSRs. I have a AEM cold air kit, poweraid TBS, banks torque tube headers, banks monster cat back, and a stage II Jet chip. It has the 6 speed in it and like most of you I'm not happy with the 4.10s. I have all but made up my mind on getting 5.13s and I don't want to start this debate again. All I want to know is what kind if highway MPG everyone with simliar set ups are getting with the 5.13s and 4.88s. I myself am very easy on the skinny pedal unless i have the need to speed up, and I do the speed limit. I can squeez over 18.5 highway MPG in NJ with the 4.10s. I want the extra power from the 5.13s but I don't want my MPG to drop down to single digits to get it. So let me Know your numbers and if I can get 15 to 16 with the way I drive and the 5.13s that's what I'm getting other wise I'm going with the 4.88s. BTW my daily comute is 30 miles mostly highway that i drive at 65mph and I wheel hard on the weekends. I want the 5.13s for the wheelin, the extra get up and go around town, and I don't want to have to shut the cruise off cause the 4.10s can't push it up a hill at 65. One more thing, I've already done all the math and know the RPMs for both gears I'm just looking for real numbers from those that have made the swap already.
thanks in advance
JT

 

If you are pulling 18mpg on 35s you are a mpg god!!!! lol!!! I would change nothing. I have 5.13s and 35s. I get 13-14 mixed.

 

Your set up is nearly identical to mine, 6 speed. CAI, headers, exhaust and a hypertech as opposed to the Jet programmer. I too get what I would consider great gas mileage on 35s, with a 45 mile each way daily commute, and I'll leave the mpg to the side as it sounds like a fish story.

2 door or 4 door? Bumpers, winch, plans for other gear?

I would assume a large part of your daily commute is highway driven. If you take 6th gear away from yourself, and running 4.10s 5th gear is going to be the same as if you had 4.88s. Not just close, but identical and you can reset your computer to give you a quick look at that portion of your mpg efficiency or run a tankful through to get an idea.

 

You don't need 5.13s for 35 inch tires. Trust me 4.88s will be just fine. That is unless you plan to go up to 37/38 inch tires. (then do the 5.13s)

 

Straight highway @ 60 or just over i get 18 with RubyDoo.

 

x2, I had 5.13's with my 35's and 6 speed and I hated them.

 

This basically the type of set up I want to eventually go with. Why do you HATE the 5.13's with the 35's and 6spd?

 

I have 5.13's with 35's and think that it's OK. RPM's are a little high at speeds above 70, but other than that I like the setup. I do alot of interstate driving and if I wasn't planning on going to 37's I would have went with 4.88's. Good thing is that I can set the cruise in 6th gear and not have to worry about gearing down on hills.

With all of that said I haven't manually checked my milage. I reset my speedo with the ProCal the other day and checked it with the GPS... it appears to be correct. I reset my MPG gauge on the the dash at the same time and it says that I'm getting 17.4 mpg. I doubt that my milage is that good, but we'll see....

 

Manually checked my MPG after work. Had 229.9 miles on my last full tank and it took 15.42 gal to fill it up. 14.9 MPG.... that was mostly interstate driving with a little bit of city/stop and go traffic. The dream gage on the dash had dropped to 16.9. It was never "right on" even before the lift, tires and gears.

 

Dunno, but when you are done with the 4.10's, send 'em to me. I am looking to replace my 3.21's for 4.10's!