37’s and 6 speed MT + Stock 4.10 Gearing

[EMS]

I don't mind the stock clutch. It's a little light but once I got use to it it was fine. If you have have stock 3.45 gears and 35" tires you probably hated the stock clutch and the light weight flywheel. That heavy CF clutch makes it easier to get going from a dead stop with those tall gears. If you switch to 4.56 gears you will be able to take you foot off the clutch without touching the gas the the JL will start rolling just fine. They were just after mph numbers with the stock gears and tires in the sport.

I have 4.10 gears and I will regear to 4.56 or 4.88. 4.10 (w33's) is just barely not enough to get much use out of 6th gear. I gotta be doing over 80 on flat ground to be up in the power band and able to hold 6th. I almost never get to 80+ mph so 6th is never used. I would like to be sitting close to 2500 rpm at 80mph. This little 3.6 just isn't very happy below 2300.

WOW.... what a difference. 3.6L pentastar/CF clutch/4.56 gears/35" tires appears to be the perfect match... way better than the stock JL sport. 6th is usable again as an overdrive, 1st is peppy at idle and just a touch of the gas makes it jump. Not sure how this is possible, but it even seems the powerband pulled lower. It has to drop below 1500 rpm to bog now, where before it would happen above 2000. Anyway, a good investment... now it drives as good as it looks.

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[Winder]

WOW.... what a difference. 3.6L pentastar/CF clutch/4.56 gears/35" tires appears to be the perfect match... way better than the stock JL sport. 6th is usable again as an overdrive, 1st is peppy at idle and just a touch of the gas makes it jump. Not sure how this is possible, but it even seems the powerband pulled lower. It has to drop below 1500 rpm to bog now, where before it would happen above 2000. Anyway, a good investment... now it drives as good as it looks.

I imagine its a lot more fun to drive now. 4.56 gears are just about perfect for 35" tires assuming you don't have a ton of added weight.

 

[ChattVol]

I went 5.13 and I also have the Centerforce clutch, drives great on an off road. 6th gear is useable again on the freeway and my mpg are back to stock. They had dropped to 11-12 with the 4.10s and 37s.

Are you driving fast at high elevations? Why were you getting 11-12mpg's running 37s on 4.10s? I have a 6 speed running 4.10s with 37s and it gets 16-17mpg on flat hwy in 5th gear at 75mph. Still gets 14-15mpg in 4th gear at 70mph.

Also, what do you mean by saying your mpg are back to stock running 37s and 5.13?

 

[urr2slo]

Are you driving fast at high elevations? Why were you getting 11-12mpg's running 37s on 4.10s? I have a 6 speed running 4.10s with 37s and it gets 16-17mpg on flat hwy in 5th gear at 75mph. Still gets 14-15mpg in 4th gear at 70mph.

Also, what do you mean by saying your mpg are back to stock running 37s and 5.13?

Elevation is mainly between 1000 to 2500, occasionally up to 7000 ft. Freeway speeds normally 75-85, but my average is based on combined driving. 5th gear was worst on mpg unless going downhill and 6th was useless. Since regearing mpg’s are 16-16.5 and I can use 5th and 6th.

 

[ChattVol]

Elevation is mainly between 1000 to 2500, occasionally up to 7000 ft. Freeway speeds normally 75-85, but my average is based on combined driving. 5th gear was worst on mpg unless going downhill and 6th was useless. Since regearing mpg’s are 16-16.5 and I can use 5th and 6th.

16mpg is really good with 37s and 5.13s driving 75-85mph in the mountains. What rpm are you running at 75mph in 6th gear?

 

[urr2slo]

16mpg is really good with 37s and 5.13s driving 75-85mph in the mountains. What rpm are you running at 75mph in 6th gear?

I spend more time closer to 80, and thats around 2700-2800 rpm. Once I get over 3000 the mpg’s start to drop.

 

[Winder]

WOW.... what a difference. 3.6L pentastar/CF clutch/4.56 gears/35" tires appears to be the perfect match... way better than the stock JL sport. 6th is usable again as an overdrive, 1st is peppy at idle and just a touch of the gas makes it jump. Not sure how this is possible, but it even seems the powerband pulled lower. It has to drop below 1500 rpm to bog now, where before it would happen above 2000. Anyway, a good investment... now it drives as good as it looks.

Since you have done both the CF clutch and the re-gear, which one do you think was the most bang for the buck? If you could do only one which one would you pick?

 

[EMS]

Since you have done both the CF clutch and the re-gear, which one do you think was the most bang for the buck? If you could do only one which one would you pick?

Tough call. Both seemed necessary but for different reasons. I hated the way the stock clutch felt, way too light and it seemed to have a varying friction point depending on which gear was being shifted to/from. But if I had to pick one I would say the regear... absolutely changes the way the ride feels on 35s. It took it from having to row back to first on a rolling stop and only having 4 usable gears to being able to use 6th again on the highway. And the powerband pulled down so that the engine seems content at 1700 RPM where without the regear that speed would have caused a stall. I also added the aftermarket cold air intake recently, mostly just for the way it sounds, but it turns out there is a noticeable increase in engine performance as well.

 

[JL Fan]

Tough call. Both seemed necessary but for different reasons. I hated the way the stock clutch felt, way too light and it seemed to have a varying friction point depending on which gear was being shifted to/from. But if I had to pick one I would say the regear... absolutely changes the way the ride feels on 35s. It took it from having to row back to first on a rolling stop and only having 4 usable gears to being able to use 6th again on the highway. And the powerband pulled down so that the engine seems content at 1700 RPM where without the regear that speed would have caused a stall. I also added the aftermarket cold air intake recently, mostly just for the way it sounds, but it turns out there is a noticeable increase in engine performance as well.

What CAI did you get/recommend?

 

[EMS]

What CAI did you get/recommend?

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