4.88 gears versus 5.13 for 4 door auto jk
06-23-2011, 05:03 AM
#12
Originally Posted by jk2010mi
I searched for a quick answer to my question, but good not find one. Which gearing would be better for an auto jk if I go to 35inch tires from 33 inch tires - 4.88 or 5.13? I currently have 3.73 gears. I have been told 4.88 is good, but is 5.13 better?
06-23-2011, 06:44 AM
#13
JK Super Freak
I have run 5.13s for the last 22K mile and it was the best choice ever. I gained a few mpgs over the oem 4.10s.
I am up to 18mpgs @ 70 mph @ 2400 RPMs on the interstate on my 4 door with an auto.
I get about 15 mpgs city.
I have not had to lock out OD since I made the change to 5.13s and can actually pass people on the hwy
I am up to 18mpgs @ 70 mph @ 2400 RPMs on the interstate on my 4 door with an auto.
I get about 15 mpgs city.
I have not had to lock out OD since I made the change to 5.13s and can actually pass people on the hwy
06-23-2011, 06:52 AM
#15
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go with the 5.13s these autos need the lower gearing your axle setup can handle
i drove a 6speed 2dr JK with 4.88s and absolute loved it, so your havier and auto JKU should have at least 5.13s
i drove a 6speed 2dr JK with 4.88s and absolute loved it, so your havier and auto JKU should have at least 5.13s
06-23-2011, 07:14 AM
#17
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Originally Posted by jk2010mi
I searched for a quick answer to my question, but good not find one. Which gearing would be better for an auto jk if I go to 35inch tires from 33 inch tires - 4.88 or 5.13? I currently have 3.73 gears. I have been told 4.88 is good, but is 5.13 better?
06-23-2011, 08:45 AM
#20
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I have run 5.13s for the last 22K mile and it was the best choice ever. I gained a few mpgs over the oem 4.10s.
I am up to 18mpgs @ 70 mph @ 2400 RPMs on the interstate on my 4 door with an auto.
I get about 15 mpgs city.
I have not had to lock out OD since I made the change to 5.13s and can actually pass people on the hwy
I am up to 18mpgs @ 70 mph @ 2400 RPMs on the interstate on my 4 door with an auto.
I get about 15 mpgs city.
I have not had to lock out OD since I made the change to 5.13s and can actually pass people on the hwy
I run about 2400 rpm at 70mph w/ the Superchips 87 octane tune. I have found that if I switch to the "tow" tune, I run about 2600 rpm at 70 mph....mpg goes down a bit, but the increased sense of power is sufficient.
Inversly, I can run the mileage tune and it's got me running at 2200 rpm at 70 mph, and I notice kick downs and lack of performance on inclines. I no longer run the mileage tune as I prefer the 2400 rpm range.