37's with manual transimisson and 4.10 gears (my impression)

[cgflyer]

I know this has been discussed quite a bit by those with the automatic and many of you don't seem to mind your 37's on stock 4.10 gears. Well I just had 37's mounted on my MT JTR with stock gears and here is my impression:

First, unless I just drive much different than all the people that are saying re-gearing is a MUST, I just don't think that is true. There is a difference obviously, but I am not rushing to get new gears. Will I in the future? Probably...will I go 4.88 or 5.13? Almost definitely not. 4.56 will likely be my choice. I personally like having 6th gear as an overdrive.

So, what I notice. The JT does feel heavier, especially in the steering (I have the TSB completed with new gear/box). With 35's before, I felt like I was always hunting gears, none really felt right. 4th would wind out, but not give me much added power/acceleration above 2,500 rpms. 5th seemed almost as wimpy as 6th in some cases. With the 37's I actually find 4th gear almost perfect and I stay in 4th gear from about 35-40 mph up to almost 60 mph. It just became a very comfortable and usable gear. 5th from 55-65 or 70 mph and 6th is usable on the flats at 65 mph and up. It does not handle inclines in 6th that it could handle before, but I honestly don't think it needs to and an automatic is most definitely downshifting from 8th to 7th and probably 6th or 5th on hills too (stock gears). I have not towed with it and I am sure I will experience some issues towing, but I rarely tow anything more than 2,000 pounds and it is not a daily thing for me. RPMs relative to speed dropped by about 150-200 in each final gear.

My build so far includes (among other stuff) MetalCloak Overland fenders front and back and I think 37's look too big currently even with the added clearance of the fenders, but my MetalCloak 3.5" True Dual Rate suspension kit arrives today. I also have a Pulsar tuner...yes, this does make a difference. I have not tried the stock tune with 37's because it is irrelevant to me since I never drive it in stock. Before, I always drove it in the Economy tune unless I was towing more than my trash trailer, then I would use the Tow tune. Almost never used the Performance tune since it requires 91+ octane. The truck was perfectly drivable in the Economy tune, but I am liking it in Tow right now. I'm due for a fill up and will grab a tank of premium and try it in Performance and see what it does to mpg...in the Tow tune, I am seeing very similar mpg as with 35's in Economy.

I'm running Patagonia MT 37/12.5R70 tires (my 35's are for sale! same tire). I haven't gone off-road yet, but will try in the next few weeks.

Overall, I don't think it drives much different than with 35's. I will re-gear eventually, but will likely stay at 4.56.

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[cgflyer]

Oh, and with some very generic math...If I chose to use the Performance tune and spend $10 more a fill up, it would take roughly 150 tanks of gas to pay for a re-gear at about $1500. 200 tanks at $2000. A Pulsar is $600. If you are dying for 37's but don't know if you want to re-gear or can't afford the re-gear, the Pulsar may be a cheaper alternative.

 

[DeezJT]

Once you start adding dedicated weight, or venture out in high altitudes, you’ll notice that you might want to consider going lower than 4.56 in the future.

It will vary from user/location as each Jeep will always be different

 

[cgflyer]

Once you start adding dedicated weight, or venture out in high altitudes, you’ll notice that you might want to consider going lower than 4.56 in the future.

It will vary from user/location as each Jeep will always be different

Yeah, I definitely have added weight (bumpers, winch, rack, rtt, fenders) but hope to eliminate my rear seat for Overland trips, leaving my doors home and going with Bestop cloth doors to help regain some of what I lose with my loadout. But I also live on the East Coast and don't deal much with altitude issues now...but I will in the Spring when I take the TAT west. I will definitely be experimenting in the next few months.

 

[hjdca]

I know this has been discussed quite a bit by those with the automatic and many of you don't seem to mind your 37's on stock 4.10 gears. Well I just had 37's mounted on my MT JTR with stock gears and here is my impression:

First, unless I just drive much different than all the people that are saying re-gearing is a MUST, I just don't think that is true. There is a difference obviously, but I am not rushing to get new gears. Will I in the future? Probably...will I go 4.88 or 5.13? Almost definitely not. 4.56 will likely be my choice. I personally like having 6th gear as an overdrive.

So, what I notice. The JT does feel heavier, especially in the steering (I have the TSB completed with new gear/box). With 35's before, I felt like I was always hunting gears, none really felt right. 4th would wind out, but not give me much added power/acceleration above 2,500 rpms. 5th seemed almost as wimpy as 6th in some cases. With the 37's I actually find 4th gear almost perfect and I stay in 4th gear from about 35-40 mph up to almost 60 mph. It just became a very comfortable and usable gear. 5th from 55-65 or 70 mph and 6th is usable on the flats at 65 mph and up. It does not handle inclines in 6th that it could handle before, but I honestly don't think it needs to and an automatic is most definitely downshifting from 8th to 7th and probably 6th or 5th on hills too (stock gears). I have not towed with it and I am sure I will experience some issues towing, but I rarely tow anything more than 2,000 pounds and it is not a daily thing for me. RPMs relative to speed dropped by about 150-200 in each final gear.

My build so far includes (among other stuff) MetalCloak Overland fenders front and back and I think 37's look too big currently even with the added clearance of the fenders, but my MetalCloak 3.5" True Dual Rate suspension kit arrives today. I also have a Pulsar tuner...yes, this does make a difference. I have not tried the stock tune with 37's because it is irrelevant to me since I never drive it in stock. Before, I always drove it in the Economy tune unless I was towing more than my trash trailer, then I would use the Tow tune. Almost never used the Performance tune since it requires 91+ octane. The truck was perfectly drivable in the Economy tune, but I am liking it in Tow right now. I'm due for a fill up and will grab a tank of premium and try it in Performance and see what it does to mpg...in the Tow tune, I am seeing very similar mpg as with 35's in Economy.

I'm running Patagonia MT 37/12.5R70 tires (my 35's are for sale! same tire). I haven't gone off-road yet, but will try in the next few weeks.

Overall, I don't think it drives much different than with 35's. I will re-gear eventually, but will likely stay at 4.56.

Thanks for this info. I am going through the same process with my manual tranny JT Rubicon. I ordered the Clayton 3.5 overland plus kit and I am currently picking tires and rims. The 37 Patagonias are pretty light. What weight are your wheels ? I am looking at wheels that are 26 lbs and Goodyear Kevlar MT/R at 73 lbs.. This is roughly just over 10 lbs more per wheel/tire combo over my stock Rubicon Falken M/T 33s. I was thinking I need to go to 5:13 gears living in the mountains, but, maybe 4:88s are OK -- especially since you are happy with 4:10s on flat ground.

 

[cgflyer]

Thanks for this info. I am going through the same process with my manual tranny JT Rubicon. I ordered the Clayton 3.5 overland plus kit and I am currently picking tires and rims. The 37 Patagonias are pretty light. What weight are your wheels ? I am looking at wheels that are 26 lbs and Goodyear Kevlar MT/R at 73 lbs.. This is roughly just over 10 lbs more per wheel/tire combo over my stock Rubicon Falken M/T 33s. I was thinking I need to go to 5:13 gears living in the mountains, but, maybe 4:88s are OK -- especially since you are happy with 4:10s on flat ground.

I'm running Procomp wheels that I think weigh 25 lbs each. My wheel/tire setup on these with 315/12.5R70 Pats were definitely lighter than the stock Rubi wheels and Falken 33" MT. That was a heavy set and I think the Falkens were awful.

 

[hjdca]

I'm running Procomp wheels that I think weigh 25 lbs each. My wheel/tire setup on these with 315/12.5R70 Pats were definitely lighter than the stock Rubi wheels and Falken 33" MT. That was a heavy set and I think the Falkens were awful.

Thanks. You have a nice setup. I also have a Jan. 15 ship date from Clayton. Note: Since I ordered the 3.5" lift, I also went with the Adams 1310 driveshaft and the RockJock Carrier Bearing Spacer to help with the rear driveshaft angle.

Note: The 6th gear on our manual JTRs is higher than the 8th gear in the auto JTRs -- I think about 200 to 250 rpm or so higher at the same hwy speed. Manual gear ratios (5th - .81, 6th - .72). Auto gear rations (7th - .84, 8th - .67)... So, our hwy rpm with the manual in 6th gear should be higher than the automatics. That should help.

 

[cgflyer]

Thanks. You have a nice setup. I also have a Jan. 15 ship date from Clayton. Note: Since I ordered the 3.5" lift, I also went with the Adams 1310 driveshaft and the RockJock Carrier Bearing Spacer to help with the rear driveshaft angle.

Note: The 6th gear on our manual JTRs is higher than the 8th gear in the auto JTRs -- I think about 200 to 250 rpm or so higher at the same hwy speed. Manual gear ratios (5th - .81, 6th - .72). Auto gear rations (7th - .84, 8th - .67)... So, our hwy rpm with the manual in 6th gear should be higher than the automatics. That should help.

I knew the ratios for the MT, but didn't know exactly how they compared the AT. I opted out of the driveshaft for now, but will be adding it in a few months. I read in a different forum, that you can droop the driver's side to 28" inches until you contact the stock driveshaft and 32" on the passenger side...the MC suspension has 30" of travel. I don't think my wheeling will get me to full droop and the MC lift really doesn't net 3.5", closer to 2.5" that I am aware and I asked for their 2.5" springs up front, not sure if they are going to honor that or not. I looked into Clayton and almost went with them, but I had MC on my JKR and really liked the kit and decided to go with them again. Their shock option is much cheaper than Clayton too and their joints have more articulation, but I also really do like how responsive Clayton is in this forum. It was a tough choice. I just stuck with what I knew.

 

[cgflyer]

So with premium gas and the performance tune on the Pulsar, the Jeep drives really well in all but climbs. It was never a climbing fool with the 35's but it did ok. I can hold 65 in 6th with 70 set on the cruise control on hills I could hold 70 on before. I still think it is comfortably drivable in my economy and tow tunes and I will likely stick with those and 87 octane unless I am doing something that I think will require additional power.

 

[mstrav73]

I know this has been discussed quite a bit by those with the automatic and many of you don't seem to mind your 37's on stock 4.10 gears. Well I just had 37's mounted on my MT JTR with stock gears and here is my impression:

First, unless I just drive much different than all the people that are saying re-gearing is a MUST, I just don't think that is true. There is a difference obviously, but I am not rushing to get new gears. Will I in the future? Probably...will I go 4.88 or 5.13? Almost definitely not. 4.56 will likely be my choice. I personally like having 6th gear as an overdrive.

So, what I notice. The JT does feel heavier, especially in the steering (I have the TSB completed with new gear/box). With 35's before, I felt like I was always hunting gears, none really felt right. 4th would wind out, but not give me much added power/acceleration above 2,500 rpms. 5th seemed almost as wimpy as 6th in some cases. With the 37's I actually find 4th gear almost perfect and I stay in 4th gear from about 35-40 mph up to almost 60 mph. It just became a very comfortable and usable gear. 5th from 55-65 or 70 mph and 6th is usable on the flats at 65 mph and up. It does not handle inclines in 6th that it could handle before, but I honestly don't think it needs to and an automatic is most definitely downshifting from 8th to 7th and probably 6th or 5th on hills too (stock gears). I have not towed with it and I am sure I will experience some issues towing, but I rarely tow anything more than 2,000 pounds and it is not a daily thing for me. RPMs relative to speed dropped by about 150-200 in each final gear.

My build so far includes (among other stuff) MetalCloak Overland fenders front and back and I think 37's look too big currently even with the added clearance of the fenders, but my MetalCloak 3.5" True Dual Rate suspension kit arrives today. I also have a Pulsar tuner...yes, this does make a difference. I have not tried the stock tune with 37's because it is irrelevant to me since I never drive it in stock. Before, I always drove it in the Economy tune unless I was towing more than my trash trailer, then I would use the Tow tune. Almost never used the Performance tune since it requires 91+ octane. The truck was perfectly drivable in the Economy tune, but I am liking it in Tow right now. I'm due for a fill up and will grab a tank of premium and try it in Performance and see what it does to mpg...in the Tow tune, I am seeing very similar mpg as with 35's in Economy.

I'm running Patagonia MT 37/12.5R70 tires (my 35's are for sale! same tire). I haven't gone off-road yet, but will try in the next few weeks.

Overall, I don't think it drives much different than with 35's. I will re-gear eventually, but will likely stay at 4.56.

Don't forget the automatics are 8 speed which obviously makes a difference in this opinion as well vs a 6-speed manual


As for what gears to get, get all your goodies on your truck and do gears last as the more you ad, the lower the gear selection you may want to go. Would be cool if you could meet up with someone with the gears you want and drive their truck for a comparison, might help in your decision

 

[cgflyer]

Don't forget the automatics are 8 speed which obviously makes a difference in this opinion as well vs a 6-speed manual


As for what gears to get, get all your goodies on your truck and do gears last as the more you ad, the lower the gear selection you may want to go. Would be cool if you could meet up with someone with the gears you want and drive their truck for a comparison, might help in your decision

yeah, I would like to feel the difference between mine and one re-geared. So far, I like the drive with my tuner. My truck is already 90% built. The only thing getting added is a Gobi rack which is being shipped any time...subtractions for overlanding will be full doors, replaced with cloth doors and perhaps rear seat deletion and the goose gear storage system. I have a fairly heavy build as it stands (probably not as heavy as some). If it drives as it does now with my weight, I may actually forgo the gears for a while now. MPGs definitely suffer though in the Performance tune and I may stick with the Tow tune.

Not to hijack my own thread, but I would encourage people look into the Pulsar. I did have issues with mine, but Edge/Superchips customer service is some of the best I have ever dealt with and they have stood by their product and fixed issues when they came up. The tunes are noticeable and if you can't afford a SC (most can't), this will give you some boosted performance.

 

[bkmarks]

I have just picked up my 21 Rubicon JT with MT. I am looking at the Clayton and Metalcloak 3.5 " lifts, very curious which one is most true to a 3.5" lift.

 

[hjdca]

I have just picked up my 21 Rubicon JT with MT. I am looking at the Clayton and Metalcloak 3.5 " lifts, very curious which one is most true to a 3.5" lift.

I bought the Clayton 3.5 overland plus on Black Friday. I am still waiting for delivery, but the Falcon 2.2 SP3 adjustable shocks have been shipped. My research has shown that the Clayton is higher in the rear than the MetalCloak. Clayton philosophy is to just raise the front and back the same from stock, and MetalCloak philosophy it to raise the front 3.5 inches and only raise the back enough to make it level. The Clayton keeps the factory rake, while the MetalCloak evens everything out -- I have read posts on this forum of something like 3.5 inches in the front and 2 inches in the back for the MetalCloak. Also, looking at the videos, the Clayton looks to be a tad higher all the way around - ie. a little over 3.5" all the way around. I also liked the Clayton control arms better, but, You cannot go wrong with either kit. Both are quality companies with great reputations -- one on the East Coast and one on the West coast. It just depends on the look and rear payload you are considering.
PS. I have the MetalCloak diff skids and diff covers, and I think those are the best available right now.

 

[cgflyer]

I have just picked up my 21 Rubicon JT with MT. I am looking at the Clayton and Metalcloak 3.5 " lifts, very curious which one is most true to a 3.5" lift.

MC's 3.5 only gives about 1.5" in the rear and unfortunately loses the factory rake which I wanted to keep for towing and overlanding weight. Clayton claims that their advertised heights are dead on.

 

[Clayton Off Road]

MC's 3.5 only gives about 1.5" in the rear and unfortunately loses the factory rake which I wanted to keep for towing and overlanding weight. Clayton claims that their advertised heights are dead on.

Actually we aim for our lifts to be slightly taller than the advertised height! So a 3.5" kit is really about a 4" kit. This is both so that you're always getting the amount of lift you paid for, and also so that any heavy accessories you add on don't affect overall height too much.

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