psrivats' 2005 TJ Rubicon mild build

jjvw said:
This is what I come up with after bumping the speed up to 75mph where I am more familiar with the numbers.

33s
42rle/31.5”/3.73=2059rpm @ 75mph
42rle/31.5”/4.10=2263rpm @ 75mph
42rle/31.5”/4.56=2517rpm @ 75mph
42rle/31.5”/4.88=2694rpm @ 75mph
42rle/31.5”/5.13=2832rpm @ 75mph
42rle/31.5”/5.38=2970rpm @ 75mph

5.38 fits with my preference of 3k at 75.

If you want to get really finicky with the values, we need gps speed orn a long flat road and the rpm read from the PCM via ODBII. What you should also find is that the speed shown at the PCM is not the same as what is shown at the needle. :)
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Thanks for checking, appreciate it. I do have an obdii dongle that connects to the Torque app on the phone via bluetooth. I did not know that the rpm indicated in the gauge is different than what comes out of obdii. If were to guess, the gauge value is some sort of time averaged value to make it look less choppy? I'll go drive it today nevertheless, I like poking into this type of stuff 🙂
 
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psrivats said:
... I did not know that the rpm indicated in the gauge is different than what comes out of obdii. If were to guess, the gauge value is some sort of time averaged value to make it look less choppy? ...
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The rpm gauge appears to be accurate between the PCM and dash gauge. As best as I can tell, there is a percentage discrepancy between the PCM and the speedo gauge. The gauge reads increasingly faster than the PCM does. Mine is corrected so that GPS matches the PCM to within a few tenths of a percent. I have no reason for having done it that way other than it makes the ODO and trip OD more accurate. It also means I am driving a mile or two slower on the highway than what the needle says.
 
zebra12 said:
Would Dave do your regear and which brand gears would you use?
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Yup and he typically uses Yukon. I don't think the brand matters as much as the setup process. You really need an experienced person for this, and other than Dave and 6states, I don't know anyone else that can do a good job with the gear setup. It will be closer to the summer time though when I do it since that's when I'll be driving a whole lot on the mountain roads.

It's funny in a way because the initial re-gear (4.88s for the 32s) is how I got into this vibration mess 😂.

Edit: Paul also does gears, I think. Learned only very recently.
 
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And, you'll be screwed if the gear change makes the rear drive shaft unhappy, like mine. Your playing with fire!
 
psrivats said:
It's not possible to change only the OD gear ratio since it is a "derived" ratio from the existing other gears. You'll have to reengineer the entire transmission.


I have the factory soft top Chris.
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Figures. That is the current trend in autos I guess.
 
zebra12 said:
Is Yukon quality as good as Revolution?
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I don't know much other than that I've read on the forums. People seem to like Revolution for the consistency. But Yukon has good warranty atleast. Blaine likes to use Revolution. I wish we could get Dana/Spicer in the numerically larger ratios.


Edit: Dana Spicer does offer deep gears in TJ size (ee below example for 5.89 ratio) atleast for the 3.92 and up carrier break. Need to do some reading to see if they make a version that'll fit in the TJ Rubicon axles.

https://www.danaaftermarket.com/spi...LA&cat3=RP&cp=0&catalog=PIMS_NA&partType=PART

Edit 2: Wow, they make R&P in a lot of ratios.

Dana 30:
3.07 3.45 3.54 3.55 3.73 3.91 4.10 4.27 4.30 4.56 4.88 5.13 5.38

Dana 35:
3.07 3.27 3.55 3.73 4.10 4.11 4.56 4.88 5.13

Dana 44:
2.94, 3.07, 3.13, 3.21, 3.31, 3.36, 3.45, 3.54, 3.55, 3.73, 3.91, 3.92, 4.09, 4.10, 4.11, 4.27, 4.30, 4.55, 4.56, 4.88, 4.89, 4.90, 5.13, 5.38, 5.89

TJ specific Dana 44 link -

https://www.danaaftermarket.com/sea...DANA 44"]}]&y=2005&mk=Jeep&md=Wrangler&sort=1
 
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Q2 thread update (since last update was Jan 1) :ROFLMAO: :ROFLMAO:

42RLE .. wish I had known what a pain this was going to be. I have recently developed the torque converter shudder that seems to be happen a lot with this transmission. Just crossed 65k miles. Per Blaine, a new TC is likely needed to fix this. Doing some research now. I also have another problem that is a more recent development, noise from the solenoids whenever putting the vehicle in reverse or drive. Really loud sound. Also seems to be a "feature" with this transmission. Not sure if this is something to worry about yet.

Been driving the jeep more recently as the weather has been warming up. This winter was the 1st time I did not put the soft top on. I also left the half doors/bestop sliders on just as an experiment. Other than increased road noise, I could live with this combination permanently. I may end up selling my full doors and hard top and get garage space back. I still haven't taken a really long road trip with this combo, but I have one coming up in May. Will see how that goes.

Gears - I need to go to 5.38s, no question. Driving on hilly roads is not an enjoyable experience. I found out that Revolution is the only brand that makes thick cut 5.38s that I need with the existing factory lockers. I may end up doing this much sooner than I was anticipating, costs be damned. Yes, there is risk of potential rear vibes.

The other option is trying to figure out if there is merit in trying to adjust the shift points via a tune, and whether it's a better choice than gears overall. Need to do some research.

Might also need to go see Paul again for the shocks, but that is not too urgent.
 
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Oh man... You're going to open up the gearing can of worms again? I guess, since you have front locking hubs installed now, it should be better. I'm just bummed you're having as many issue as you are. Low mileage, old vehicle have just as many ghosts and goblins as the high mileage ones, I guess. They are just different.
 
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Mike_H said:
Oh man... You're going to open up the gearing can of worms again? I guess, since you have front locking hubs installed now, it should be better. I'm just bummed you're having as many issue as you are. Low mileage, old vehicle have just as many ghosts and goblins as the high mileage ones, I guess. They are just different.
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If I were to do this again .. I would get a manual Jeep, no questions. My life (and savings!) would have been better!

Just thinking out loud at this point, but some action needs to be taken in the summer. The shudder needs addressing soon since it annoys the crap out of me.
 
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5.38 gears are in.

verdict: they are pretty perfect with my 33x10.5 KO2 ATs. Jeep feels peppy and highway rpms are where they should be.

@jjvw - I am glad I trusted your 75mph @ 3000 rpm guideline.

edit: no new vibes of any sort front or rear. All is well. I am very glad I have hubs.
 
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psrivats said:
5.38 gears are in.

verdict: they are pretty perfect with my 33x10.5 KO2 ATs. Jeep feels peppy and highway rpms are where they should be.

@jjvw - I am glad I trusted your 75mph @ 3000 rpm guideline.

edit: no new vibes of any sort front or rear. All is well. I am very glad I have hubs.
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Do you have vibes if the hubs are locked in?
 
Wildman said:
Do you have vibes if the hubs are locked in?
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Yup - but same as before that I had with 4.88s, I did not get any *new* vibrations.

Past 62-63 or so they start and they are liveable with for short periods of time, but they are there with some dull intensity at any speed past that. I have tried everything I could and I cannot resolve them and hubs were the only option to be able to do highway speeds.
 
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Okay that helps if other people want to go there. I find this interesting that this happens.
 
psrivats said:
5.38 gears are in.

verdict: they are pretty perfect with my 33x10.5 KO2 ATs. Jeep feels peppy and highway rpms are where they should be.

@jjvw - I am glad I trusted your 75mph @ 3000 rpm guideline.

...
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I'm a strong believer in it. Is a very rare case where someone (weirdo) thought 3k@75mph was over geared.
 
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