6 speed with 37s on a rubicon

rustyshakelford

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Haven’t seen this combo yet. Curious how the drivability is. Live close to sea leve but planning a Moab trip in april. Would prefer not to regear in case I get the lifetime waranty but f/r gear sets are only a grand so it’s tempting.

Brett





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vavaroutsos

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Haven’t seen this combo yet. Curious how the drivability is. Live close to sea leve but planning a Moab trip in april. Would prefer not to regear in case I get the lifetime waranty but f/r gear sets are only a grand so it’s tempting.

Brett
You'll probably want to regear to 5.13. I find the factory gearing too tall with 33" tires on my manual Rubicon. Both 5th and 6th gears are overdrive.
 

WrongWheelDrive

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Lots of people are running this setup, Does it work - YES. Could it benefit from a regear - YES. I personally will not be regearing unless I go bigger then 37s.
Wrm81dSwSeOByZow9REZLw.jpg
 
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Lots of people are running this setup, Does it work - YES. Could it benefit from a regear - YES. I personally will not be regearing unless I go bigger then 37s.
Wrm81dSwSeOByZow9REZLw.jpg
So you’re happy with the performance of the 37s in that it’s tolerable? Would rather scrimp and save to do the 4.88 before Moab but again with the warranty concerns

You'll probably want to regear to 5.13. I find the factory gearing too tall with 33" tires on my manual Rubicon. Both 5th and 6th gears are overdrive.
With the 4.10s and 37s it changes it to around 3.63 which isn’t horrible. 5.13 might be a little much was checking out the 4.88 if I go that route

Brett
 

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So you’re happy with the performance of the 37s in that it’s tolerable? Would rather scrimp and save to do the 4.88 before Moab but again with the warranty concerns



With the 4.10s and 37s it changes it to around 3.63 which isn’t horrible. 5.13 might be a little much was checking out the 4.88 if I go that route

Brett
Yeah its def tolerable, going up a hill you will need to downshift where maybe you didnt have to with 33s. I live in the northeast with lots of hills and its not bad at all.

If I was going to regear Id def skip right over 4.88s your not going to see enough of a dif for the cost...def 5.13s
 

vavaroutsos

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So you’re happy with the performance of the 37s in that it’s tolerable? Would rather scrimp and save to do the 4.88 before Moab but again with the warranty concerns



With the 4.10s and 37s it changes it to around 3.63 which isn’t horrible. 5.13 might be a little much was checking out the 4.88 if I go that route

Brett
Brett, best thing I can say is drive your Jeep a bit first, then decide for yourself. The 6 speed manual is very wide range with a low first gear. I hardly use 6th with 33" tires and I'm getting about 22 mpg combined. I will regear to 4.88 when I put my 35" tires on. I would personally go 5.13 with 37". I also thought that's too short at first, but after putting some miles on, I changed my opinion. I would rather have the low 1st for crawling and be able to use 6th on the freeway than use 1st on the street and 6th only on downhill.
 
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Brett, best thing I can say is drive your Jeep a bit first, then decide for yourself. The 6 speed manual is very wide range with a low first gear. I hardly use 6th with 33" tires and I'm getting about 22 mpg combined. I will regear to 4.88 when I put my 35" tires on. I would personally go 5.13 with 37". I also thought that's too short at first, but after putting some miles on, I changed my opinion. I would rather have the low 1st for crawling and be able to use 6th on the freeway than use first on the street and 6th only on downhill.
Thanks for the tips. This was ordered out of state and I’m trying to make my decisions on what tires to order. The 35s are easy and simple but will I regret getting them that small? I’m trying to get this as complete as possible when I buy it. The dealer is buying my factory tires hence the reason to get that part ironed out. If I don’t like it, we can always regear. I really think the 5.13s would be great after hearing from y’all but how would it affect the warranty. They cost about $3300 and would hate to lose coverage on the axles.

Brett
 

vavaroutsos

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Thanks for the tips. This was ordered out of state and I’m trying to make my decisions on what tires to order. The 35s are easy and simple but will I regret getting them that small? I’m trying to get this as complete as possible when I buy it. The dealer is buying my factory tires hence the reason to get that part ironed out. If I don’t like it, we can always regear. I really think the 5.13s would be great after hearing from y’all but how would it affect the warranty. They cost about $3300 and would hate to lose coverage on the axles.

Brett
You should be able to get a gear swap for less than that. Dana/Spicer gear sets can be found for $200, and the master install kits are about $250 (you really don't need most of the kit, so there is potential savings here). Installation should only be about $500/axle and even less if you pull the axles out. I would think if you use Dana/Spicer gears, and had a dealer install them, your warranty wouldn't be affected. Now if you installed taller gears, I could see them saying it caused more stress on the drive train. Either way, larger tires increase stress on the axles (regardless of gearing) and brakes, so you might still have a warranty issue there.
 
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You should be able to get a gear swap for less than that. Dana/Spicer gear sets can be found for $200, and the master install kits are about $250 (you really don't need most of the kit, so there is potential savings here). Installation should only be about $500/axle and even less if you pull the axles out. I would think if you use Dana/Spicer gears, and had a dealer install them, your warranty wouldn't be affected. Now if you installed taller gears, I could see them saying it caused more stress on the drive train. Either way, larger tires increase stress on the axles (regardless of gearing) and brakes, so you might still have a warranty issue there.
The 3300 was for the lifetime warranty. I can get the gears for 1k for front and back and have a buddy that will install them for $400 total. Starting to look much more tempting.

Brett
 

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The 3300 was for the lifetime warranty. I can get the gears for 1k for front and back and have a buddy that will install them for $400 total. Starting to look much more tempting.

Brett
I’m $1800 into a regear F/R and I used genuine Dana/Spicer gears and overhaul sets.
 

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And no issues with warranty?
I didn’t exactly try to get written approval from FCA. But I can’t see how they could deny warranty for any part of the vehicle besides the actual gear sets.
 

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Oh no. With 37's your axles, steering, wheel bearings, drive train etc. are all affected with more stress from the bigger tires. But these things are pretty strong and most likely will not give a problem as long as you dont do extreme rock crawling. But dont go back to jeep with a broken track bar or the like expecting any sort of coverage. Whenever you modify a aspect of the vehicle, any affected or plausibly affected component loses any warranty coverage.

One time I changed the factory stereo on a Nissan and they refused to cover a bad airbag light since I removed the dash panel with the warning light attached.
 

Midwest22

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I’m $1800 into a regear F/R and I used genuine Dana/Spicer gears and overhaul sets.
Your set up is amazing (I've got an all white Rubi so I guess Im a bit biased). Im thinking of going the same route with the Mopar wheels although I may not go the extra mile and get the simulated beadlock powdercoated...or I might, depending on how I feel when I mount them ;). Question: I see you regeared, yet you only went up to 35's. Is this because you're eventually going to 37's? Reason for asking is that Im thinking of jumping right to 37's with the Mopar beadlocks (simulated).

Also, would you happen to have a photo looking down the side of your Jeep that shows how far the wheels extend from the fenders?
 

DesertsJL

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Your set up is amazing (I've got an all white Rubi so I guess Im a bit biased). Im thinking of going the same route with the Mopar wheels although I may not go the extra mile and get the simulated beadlock powdercoated...or I might, depending on how I feel when I mount them ;). Question: I see you regeared, yet you only went up to 35's. Is this because you're eventually going to 37's? Reason for asking is that Im thinking of jumping right to 37's with the Mopar beadlocks (simulated).

Also, would you happen to have a photo looking down the side of your Jeep that shows how far the wheels extend from the fenders?
I went with 35’s because they are a bit more street worthy and I plan to drive the Jeep a bit before I bang it up off road. I plan to go bigger on the tires in the future.

I chose the Mopar wheels because they have a slight positive offset. Most all wheels have a neutral or negative offset and push the tires too far out of the fender for my taste.

EC20ED50-3A4C-436D-B95C-8E936DA109E1.jpeg
 

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