What gearing do I have and can an upgrade wait?

[dylansalrin]

I feel a little stupid asking this because I should know better but with my new lj, it is completely different from my old SE. My SE had 4.11 gears and a manual tranny.

What gearing does my 05 lj rubicon have in the diffs? It is an automatic. Im asking because I heard that rubicon packages came with 4.10s but also heard that all ljs have the 3.73.

Im buying 35s tomorrow (really 34.2s) and am wondering how much of an impact that will make? I run 31s right now with no issue getting from place to place and getting up to speed. I do mostly highway driving.

thanks

 

[Fouledplugs]

I feel a little stupid asking this because I should know better but with my new lj, it is completely different from my old SE. My SE had 4.11 gears and a manual tranny.

What gearing does my 05 lj rubicon have in the diffs? It is an automatic. Im asking because I heard that rubicon packages came with 4.10s but also heard that all ljs have the 3.73.

Im buying 35s tomorrow (really 34.2s) and am wondering how much of an impact that will make? I run 31s right now with no issue getting from place to place and getting up to speed. I do mostly highway driving.

thanks

Start here.
https://jeep.custhelp.com/app/jeep/eqlisting_detail/

But if you are not the orginal owner, keep in mind the PO could have changed the differential gearing changed. So to verify you will need to pull the differential cover and check the ring gear. It should be stamped with the gear ratio. I would check front and rear. Some folks will do a rear gear change and not a front..

 

[dylansalrin]

Start here.
https://jeep.custhelp.com/app/jeep/eqlisting_detail/

But if you are not the orginal owner, keep in mind the PO could have changed the differential gearing changed. So to verify you will need to pull the differential cover and check the ring gear. It should be stamped with the gear ratio. I would check front and rear. Some folks will do a rear gear change and not a front..

I bought it with 50k miles bone stock from an old couple in Oregon just after they moved from cali ha. I doubt it had any ratio changed as it still had the original factory TIRES on from 2005

 

[dylansalrin]

That link helped though thank you. It has 4.11s like I thought


Sent from my iPhone using Tapatalk

 

[Jerry Bransford]

That link helped though thank you. It has 4.11s like I thought

It's gonna be a dog with those 33's and 4.10 with your automatic. You'll be asking about ratios to change the axles to once you've had it a while. Nothing less than 4.88, 5.13 would be ideal. Yes, for 33's. Go 5.38 (which you can do with your f/r Dana 44 axles) if you see 35's in your future.

 

[dylansalrin]

It's gonna be a dog with those 33's and 4.10 with your automatic. You'll be asking about ratios to change the axles to once you've had it a while. Nothing less than 4.88, 5.13 would be ideal. Yes, for 33's. Go 5.38 (which you can do with your f/r Dana 44 axles) if you see 35's in your future.

Thanks Jerry! Yea picking up 35s not 33s. so 5.13s is the plan.

 

[StG58]

It's gonna be a dog with those 33's and 4.10 with your automatic. You'll be asking about ratios to change the axles to once you've had it a while. Nothing less than 4.88, 5.13 would be ideal. Yes, for 33's. Go 5.38 (which you can do with your f/r Dana 44 axles) if you see 35's in your future.

He's getting 35's so just jump to the 5.38's...

 

[dylansalrin]

you're saying 5.38s instead of 5.13s? so this would be all I needed: http://rover.ebay.com/rover/1/711-5...0001&campid=5337789113&icep_item=272563506517

 

[Rob5589]

Yes, 5.38 since you have F&R 44's. Those 4.10's and 35's are gonna suck so prepare yourself. 2700 rpm's at 100 The deep over drive puts that trans in a funky conundrum, 1900 at 70 in od, or 2750 at 70 in drive. Plan on using 1-3 and skipping the od altogether.

 

[dylansalrin]

Yes, 5.38 since you have F&R 44's. Those 4.10's and 35's are gonna suck so prepare yourself. 2700 rpm's at 100 The deep over drive puts that trans in a funky conundrum, 1900 at 70 in od, or 2750 at 70 in drive. Plan on using 1-3 and skipping the od altogether.

Ok good to know. So until I can get it in the shop to regear, should I just flip the OD off button?

 

[Rob5589]

Would be a good idea. If you are running down the fwy on flat ground it will be fine. If you have even minimal hills to climb leave it off so it does not constantly downshift.

 

[Andy5150]

Ok good to know. So until I can get it in the shop to regear, should I just flip the OD off button?

Turning off the od will help on the highway, but the Jeep is still going to be a stone taking off from a light. It's also stressing the transmission more, because every gear will be taller. It's exactly the same as towing a trailer.

 

[dylansalrin]

Turning off the od will help on the highway, but the Jeep is still going to be a stone taking off from a light. It's also stressing the transmission more, because every gear will be taller. It's exactly the same as towing a trailer.

So that stress on the tranny will be fixed with the regear?

 

[Rob5589]

Yes

 

[Jerry Bransford]

So that stress on the tranny will be fixed with the regear?

Yes. And don't let the shop yahoos doing the gear installation talk you into anything other than 5.38. No matter what malarkey they try to convince you of.

 

[Fouledplugs]

Yes. And don't let the shop yahoos doing the gear installation talk you into anything other than 5.38. No matter what malarkey they try to convince you of.

Agreed. It is simple math, stick with getting it geared correctly. You and your Jeep will be happy that you did.

 

[dylansalrin]

Thank you everyone for the input!. Sorry I had to make ANOTHER gear thread but it is much appreciated


Sent from my iPhone using Tapatalk

 

[Fouledplugs]

Thank you everyone for the input!. Sorry I had to make ANOTHER gear thread but it is much appreciated


Sent from my iPhone using Tapatalk

You are welcome. Good luck.

 

[Andy5150]

Yes. And don't let the shop yahoos doing the gear installation talk you into anything other than 5.38. No matter what malarkey they try to convince you of.

THIS.........don't make 1200-1500$ mistake by letting a shop tell you that 5.38 will have screaming down the highway at 4000rpm.I know 2 guys who made the mistake. Oh, they say it's ok.....as they both still have to turn off on the highway. Gearing is one of the few things where "ok" , and "perfect " are the same price....so what do you pick?