Jeep Wrangler Forum

Jeep Wrangler Forum (http://www.wranglerforum.com/)
-   JK General Discussion Forum (http://www.wranglerforum.com/f274/)
-   -   3.21 Gear Threads- Summary List (http://www.wranglerforum.com/f274/3-21-gear-threads-summary-list-209000.html)

JeepHerz 01-02-2013 12:31 PM

3.21 Gear Threads- Summary List
 
It would appear I am obsessed about my 3.21 gearing. I've assembled all the 3.21 threads I had on my subsciption list for future reference for anyone searching. Some of these are a re-gear ratio thread but I've included them since many people are re-gearing FROM 3.21s. I am sure I am missing some but here you go.
I just need one person to bump me so I can reference this list later too. :D


(All this and still not sure 4.56s will fix my problem.)
  1. http://www.wranglerforum.com/f33/3-2...on-208303.html
  2. http://www.wranglerforum.com/f33/why...6s-205404.html
  3. http://www.wranglerforum.com/f33/any...es-161999.html
  4. http://www.wranglerforum.com/f33/4-5...-a-205930.html
  5. http://www.wranglerforum.com/f33/35-...rs-194880.html
  6. http://www.wranglerforum.com/f33/is-...ad-190693.html
  7. http://www.wranglerforum.com/f33/201...ts-173023.html
  8. http://www.wranglerforum.com/f33/who...cs-139714.html
  9. http://www.wranglerforum.com/f33/35s...1s-177231.html
  10. http://www.wranglerforum.com/f33/201...st-176285.html
  11. http://www.wranglerforum.com/f33/35-...gh-169667.html

WatchThis! 01-02-2013 12:38 PM

You have an unhealthy habit.

JeepHerz 01-02-2013 12:45 PM

Quote:

Originally Posted by WatchThis! (Post 3172842)
You have an unhealthy habit.

:D
No kidding. I need a new hobby.

Bilge 01-02-2013 01:09 PM

It's good to see I'm not the only one obsessing over this addiction called Jeep.

ranjr 01-02-2013 06:01 PM

Quote:

Originally Posted by JeepHerz
All this and still not sure 4.56s will fix my problem.

Maybe it's mentioned in another thread but what exactly is your problem?

kjeeper10 01-02-2013 06:04 PM

:popcorn:

Nobozos84 01-02-2013 06:39 PM

Love this !

kramer2k 01-02-2013 07:04 PM

I'm thinking I need to regear my 4.10 down to 3.21.
Gas is killing me! :hide:

Thanks for the links. :angel:

JeepHerz 01-02-2013 07:12 PM

Quote:

Originally Posted by ranjr (Post 3174220)
Maybe it's mentioned in another thread but what exactly is your problem?

3.21 lug. I only have 305/70/17s KM2s. Procal'ed and set to correct/actual tire size. The tranny upshifts way too early- to too low an RPM- and it holds it. Its determined to drop into 4th gear at 40/1200-1400 RPMs. The power disappears- you can hear the engine lug. I've looked at my RPMs before and seen 1000 RPMs registered. I can give it gas to downshift- but within seconds it upshifts again. I know I can pop it into the correct gear- but I bought an auto. for a reason. I've tried re-setting to "relearn" my driving style- and I've tried re-setting to a larger tire to trick it. I drive 90% city so I spend most of my time between 30-45 MPH- the lug-ly spot. It did not do this stock.
I received 4.56s gears for Christmas. I know it will give me more git-up and I want the better ratio for crawling. But someone pointed out the higher RPMs might just stick me into 5th instead of 4th at 40. Making it worse-not better. Nothing is available on the 2012s for the shift points. I wish someone had a gear chart other than 70 MPH- I'd have a better idea of where I'd be.

JeepHerz 01-02-2013 07:15 PM

Quote:

Originally Posted by kramer2k (Post 3174544)
I'm thinking I need to regear my 4.10 down to 3.21.
Gas is killing me! :hide:

Thanks for the links. :angel:

Not so fast. I get a whopping 14 MPG. Stepping on the throttle to correct the upshifting I am sure. And I drive mostly city. Even on a trip to Vegas (flat; all freeway) I only averaged 16.9 MPG.

kramer2k 01-02-2013 07:19 PM

I was just joshing you. :p But I hear ya.

My mileage is horrendous, but it doesn't bother me. I get 14MPG too. You gotta pay to play and I knew that coming in.

But I feel for you with that gear setup and the power inadequacies.

ranjr 01-02-2013 07:21 PM

What's the tallest tire you'll ever run and what RPM do you want to turn at what speed in 5th? It only takes math to figure out the needed ratio.

You think yours shifts too early and I think mine shifts too late. Mine holds to 3000 in pretty much every gear.

JeepHerz 01-02-2013 07:57 PM

??? You're at 3000? There isn't a scratching head smiley.
5th isn't too much of a concern- I know I'll be at about 2600 RPMs from the chart. Given the pancake flat torque curve that won't bother me. It's the lower gears/speeds that are a concern. I don't drive many miles so I'll have the 305/70s for a long time.
I actually found this. Sjchouery kindly sent me this before the holidays and I utterly forgot....
Gear Ratio Calculator
Going to go home and play.

bengen1 01-02-2013 08:21 PM

So there is the Procal trick that I don't think anyone has tried, see post #57 done with a pre 12 using a procomp tool.
http://www.wranglerforum.com/f33/aev...-138605-3.html

kramer2k 01-02-2013 08:23 PM

Quote:

Originally Posted by JeepHerz (Post 3174838)
??? You're at 3000? There isn't a scratching head smiley.

http://www.v6performance.net/forums/...es/thinker.gif

:D

Cool gear calculator.

ranjr 01-02-2013 09:13 PM

Quote:

Originally Posted by JeepHerz
??? You're at 3000?

Yes, and it normally runs up to 4000 or so getting on the interstate between shifts. I generally have to let off to get it into 5th. I'm running 35s (well 315/70s) with 4.10s. I do not drive mine everyday and as long as it gets me to the wheeling spot, I'm good!

kjeeper10 01-02-2013 09:30 PM

Quote:

Originally Posted by kramer2k
I'm thinking I need to regear my 4.10 down to 3.21.
Gas is killing me! :hide:

Thanks for the links. :angel:

Oh no he didn't :p

JeepHerz 01-02-2013 09:54 PM

Quote:

Originally Posted by bengen1 (Post 3174954)
So there is the Procal trick that I don't think anyone has tried, see post #57 done with a pre 12 using a procomp tool.
http://www.wranglerforum.com/f33/aev...-138605-3.html

Thanks for that link. (See Post #64 for the link). Hadn't seen that one. After reading it my head hurts- but interesting stuff about the TCM.
Ranjr- maybe this will work for you? We don't see the initial post/questions from AEV but the problem seemed to be over-reving. (My Jeep doesn't over-rev- it shifts early). Maybe you need a re-reset?
Unless you prefer driving angry. Like you stole it.

ranjr 01-02-2013 10:19 PM

Quote:

Originally Posted by JeepHerz

Thanks for that link. (See Post #64 for the link). Hadn't seen that one. After reading it my head hurts- but interesting stuff about the TCM.
Ranjr- maybe this will work for you? We don't see the initial post/questions from AEV but the problem seemed to be over-reving. (My Jeep doesn't over-rev- it shifts early). Maybe you need a re-reset?
Unless you prefer driving angry. Like you stole it.

I'll take a look.

ztman 01-21-2013 12:34 PM

Bump for jeepherz, who did a heck of a job researching ratios

Dick Blonov 01-21-2013 12:46 PM

Jeepherz, ever try to slap it down to 4th as the max gear (not leave it in D)? I have a 3.21 auto (285/75R16). It does seem to shift different than in D (or my butt dyno needs a tune up).

Not sure if this good read was posted before.

DB

ohioviper 01-21-2013 01:49 PM

I think I have already posted in most of those threads but. I am very happy with 3:21 /3.6 auto and 33" DT. Im still getting around 20 mpg and couldnt be happier with fuel economy and power. You need to take advantage of the manual control Jeep gave you and slap that shifter for the gear you want when pulling hills or towing.

2013 sport s 01-21-2013 06:24 PM

I have the 3.21 with the 6 speed and travel 20 miles one way daily and haven't had any problems the only catch is 6th is a great overdrive gear but get to speed in 5th first..

JeepHerz 01-21-2013 06:32 PM

I don't have any issues on the freeway actually- but I do pop it in 4th for the hills or mountains thanks. I am not crazy about driving it in "manual" for city driving (where I have most of the issues.) You can be in 2nd gear at 3000 RPMS and barely notice. What gear am I in? LOL. I need some engine noise, a clutch and a normal torque curve to enjoy shifting.
Thanks for the read DB- I'll have to kick my feet up and have a glass of wine before I can get through it. Or a Shock Top Midnight Ale. Almost 5pm...hm.....

cornfedksboy 01-21-2013 06:36 PM

subscribe

MichaelEdwardsDO 04-29-2013 05:35 PM

I now share op's obsession

Xcrossbow 04-29-2013 08:34 PM

Just came back from Jeep Beach. Google maps says that my home to Daytona Speedway is 260 miles using my chosen route (@100 miles of country road 55mph, @160 miles of Interstate).

Speedometer has not yet been recalibrated for my 35's. Driving down, with 1500 miles of usage on the MPG "estimator" I started out with a reading of 13.1. Driving rules were to stay at or around 58mph in 55 MPH areas and 63 MPH in the 65 & 70 MPH areas both on the uncalibrated speedometer. When I arrived at Daytona my MPG average had climbed to 16.3 MPG. I was actually pretty happy with this even if the "estimator" is only an estimate.

Returning home I reset the MPG "estimator" to zero and my average was 17.3 MPG when I arrive home using the same return route and driving by the same "rules". Again I was pretty happy.

All in all I have been very satisfied with the 3.21 but the Jeep is not my daily driver and I have 2 other vehicles that can give me my occasional torque fix. If I feel the 3.21 lug coming on I will usually manually shift the automatic down a gear or speed up to get thru it.

A question I do have is if my unrecalibrated speedometer is slow because of the bigger tires does that mean that the MPG "estimator" is off and slow or lower also?

Right now, I would not be able to justify the cost of a re-gearing.

JeepHerz 04-29-2013 10:41 PM

I suppose I could up-date my thread: no more 3.21s. Re-geared to 4.56s and LOVE it. Now most upshifting drops me to 1500 RPMs minimum (as opposed to 1200). Bye Bye 3.21 lug!

MichaelEdwardsDO 04-29-2013 11:12 PM

Quote:

Originally Posted by JeepHerz (Post 3699416)
I suppose I could up-date my thread: no more 3.21s. Re-geared to 4.56s and LOVE it. Now most upshifting drops me to 1500 RPMs minimum (as opposed to 1200). Bye Bye 3.21 lug!

What brand of ring and pinion gears did you choose?

JeepHerz 04-30-2013 11:29 AM

G2. 4.56s were hard to find.
http://www.g2axle.com/Ring-and-Pinio...nion-gear.aspx


All times are GMT -5. The time now is 11:58 PM.