Another Gearing Question.....

DC0046

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Sorry for another question regarding gearing. My jeep is a 2004 Rubicon with an automatic and with 33 inch tires. I am getting ready to pull the trigger on re-gearing because I would like to drive at highway speeds without constant shifting. I went to the shop today to discuss this again with them. This shop is a reputable shop here in OKC that specializes in Jeeps and four wheel drive vehicles. They recommend Yukon gears and were concerned that with the stock axles the pinion gear in 5:13s would be very small. He called Yukon and based on my primary usage being on the road with light trails thought the 4:88 would be a better choice and the pinion gear would be larger. Yukon agreed that due to the size of the pinion, the 4:88 would be stronger.

I know @Chris and @Jerry Bransford have a lot of knowledge as do some of others on this forum do and would like a bit a feedback. The out the door cost on the Yukons was 1,669 with labor and tax. Sorry for bringing this up again, but want to get this right.

Thanks for the help.
 
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4.88 is solid advice, that will be your ideal gear ratio.

I also have a 2004 with an automatic and 33" tires. I put 4.88 gears in it over a year ago, and absolutely love it. It drives perfectly on the highway now, without constantly shifting like it would before.
 
4.88 is solid advice, that will be your ideal gear ratio.

I also have a 2004 with an automatic and 33" tires. I put 4.88 gears in it over a year ago, and absolutely love it. It drives perfectly on the highway now, without constantly shifting like it would before.
Thanks Chris.
 
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No problem! For 33" tires and the 42RLE transmission, 4.88 is the perfect gear ratio. You'll be very happy with it.
 
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Sorry for another question regarding gearing. My jeep is a 2004 Rubicon with an automatic and with 33 inch tires. I am getting ready to pull the trigger on re-gearing because I would like to drive at highway speeds without constant shifting. I went to the shop today to discuss this again with them. This shop is a reputable shop here in OKC that specializes in Jeeps and four wheel drive vehicles. They recommend Yukon gears and were concerned that with the stock axles the pinion gear in 5:13s would be very small. He called Yukon and based on my primary usage being on the road with light trails thought the 4:88 would be a better choice and the pinion gear would be larger. Yukon agreed that due to the size of the pinion, the 4:88 would be stronger.

I know @Chris and @Jerry Bransford have a lot of knowledge as do some of others on this forum do and would like a bit a feedback. The out the door cost on the Yukons was 1,669 with labor and tax. Sorry for bringing this up again, but want to get this right.

Thanks for the help.
The pinion gear on 5.13 gears is well proven and the way it and the ring gear were designed to mesh together, they have the same surface area of meshing contact that a 4.88 has. Many shop people just repeat what they've heard without first-hand knowledge.

4.88 would be ok for 33's with your 42RLE automatic but I'm coming to the conclusion that when it's available. 5.13 is a better choice for. Especially that your Rubicon has Dana 44 axles front and rear. 5.13 is EXTREMELY well tested and proven in the Dana 30 and Dana 44 axles, don't let that shop guy scare you off of them. If it were me, I'd choose 5.13 for those 33's. The very slightly higher rpms produced 5.13 over 4.88 will be appreciated.

When I can, I'm regearing my Rubicon to 5.38 to replace its current 4.88 gearing which is simply not enough gear for its 35's. I'd go deeper than 5.38 if I could but 5.38 is as low as you can go with the Rubicon lockers.

Not to mention that shop can improve on that $1669 cost if you push them harder. :)
 
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The pinion gear on 5.13 gears is well proven and the way it and the ring gear were designed to mesh together, they have the same surface area of meshing contact that a 4.88 has. Many shop people just repeat what they've heard without first-hand knowledge.

4.88 would be ok for 33's with your 42RLE automatic but I'm coming to the conclusion that when it's available. 5.13 is a better choice for. Especially that your Rubicon has Dana 44 axles front and rear. 5.13 is EXTREMELY well tested and proven in the Dana 30 and Dana 44 axles, don't let that shop guy scare you off of them. If it were me, I'd choose 5.13 for those 33's. The very slightly higher rpms produced 5.13 over 4.88 will be appreciated.

When I can, I'm regearing my Rubicon to 5.38 to replace its current 4.88 gearing which is simply not enough gear for its 35's. I'd go deeper than 5.38 if I could but 5.38 is as low as you can go with the Rubicon lockers. :)
Thanks Jerry. What are your thoughts on the Yukon gears?
 
Thanks Jerry. What are your thoughts on the Yukon gears?
Yukon is fine. My personal preference is Revolution Gear but Yukon would be ok too. And since Yukon sources their gears from a few factories in S. Korea, it wouldn't surprise me if the Yukon gears you happened to get had the same Circle K manufacturer that Revolution Gear uses. The best manufacturers of R&P gears available at this time. :)
 
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I need an education. I have a 2001 tj 4.0 w/35's, a Dana 35 3.07 rear and a 3 sp auto. (I have a Dana 44 4.88 going in Friday).
It's a moot point now but with the 3.07 gear can I drive on the street in D2? RPM at 65= 3250. I know there must be a reason not to do it but I can't figure it out.
Thanks
Jim
 
I need an education. I have a 2001 tj 4.0 w/35's, a Dana 35 3.07 rear and a 3 sp auto. (I have a Dana 44 4.88 going in Friday).
It's a moot point now but with the 3.07 gear can I drive on the street in D2? RPM at 65= 3250. I know there must be a reason not to do it but I can't figure it out.
Thanks
Jim
3250 rpms is fine, I used to drive mine at that rpm all the time after I converted to the 32RH from my previous 5-speed with its 4.88 gearing and 35's.

And for 35's and your 32RH, you do NOT want to regear to 4.88. For your 3-speed automatic which does not have an overdrive, you need to go with 4.56 gearing. Really, 4.56 is the appropriate ratio for 35's, 4.0L engine, and the 32RH. :)
 
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3250 rpms is fine, I used to drive mine at that rpm all the time after I converted to the 32RH from my previous 5-speed with its 4.88 gearing and 35's.

And for 35's and your 32RH, you do NOT want to regear to 4.88. For your 3-speed automatic which does not have an overdrive, you need to go with 4.56 gearing. Really, 4.56 is the appropriate ratio for 35's, 4.0L engine, and the 32RH. :)
Thanks Jerry. I'm commited to the 4.88 now ($ spent). I'll have to live with it for a year or so. Lesson learned - ask first.

Jim
 
@DC0046, 5.13's all the way. 4.88 is certainly usable but the 5.13 would work better. That price seems a bit high for gear only swap. What was their price break down parts and labor?

@RetiredJim, like Jerry said, 4.56 is the better way to go with the 3 spd. 4.88 won't be bad if you keep it at 65ish which would be around 3100. The good part is if you do go to 4.56 you should be able to sell those 88's pretty easily.
 
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@DC0046, 5.13's all the way. 4.88 is certainly usable but the 5.13 would work better. That price seems a bit high for gear only swap. What was their price break down parts and labor? $2384 for a G2 Dana 44 complete axle assembly with 4.88, 33 spline crome moly, ARB locker, disc brakes, freight. It was on sale and hard to resist.

@RetiredJim, like Jerry said, 4.56 is the better way to go with the 3 spd. 4.88 won't be bad if you keep it at 65ish which would be around 3100. The good part is if you do go to 4.56 you should be able to sell those 88's pretty easily.
 
@DC0046, 5.13's all the way. 4.88 is certainly usable but the 5.13 would work better. That price seems a bit high for gear only swap. What was their price break down parts and labor?

@RetiredJim, like Jerry said, 4.56 is the better way to go with the 3 spd. 4.88 won't be bad if you keep it at 65ish which would be around 3100. The good part is if you do go to 4.56 you should be able to sell those 88's pretty easily.
He didnt break it down between labor and parts. I know their shop rate is $110 per hour and the Yukon gears are a bit more expensive than the G2s that they normally put in.
 
Thanks Jerry. I'm commited to the 4.88 now ($ spent). I'll have to live with it for a year or so. Lesson learned - ask first.

Jim
You are not committed until they have started the install. You will NOT like the 4.88 gearing with the 35's and your 32RH. I ran that combination for several years after converting to the 32RH. It ended up slowing my highway cruising speed from 65-70 to 55-60. The shop may grumble but so what. Accepting 4.88 would be a mistake at this point before the job has started.
 
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He didnt break it down between labor and parts. I know their shop rate is $110 per hour and the Yukon gears are a bit more expensive than the G2s that they normally put in.
That price is for the entire Dana 44 rear axle assembly to replace my Dana 35 with brakes, gears and locker installed in it but not installed in the jeep.