Best gear ratio for Dana 30 front and Dana 44 rear?

[g.hayduke]

I am in Texas Houston area where everything is flat as a tile. 2500RPM provides enough punch to drive at 70MPH and I can get to 80MPH pretty easily.

That's your experience at sea level on flat terrain. As long as that's all your Jeep sees, you're good.

Would you like your Jeep to perform well under those ideal conditions and also perform acceptably at elevation with some hills on occasion? If so, you'll need more power which means more RPM which means lower gearing. If it'll never leave Texas, you're good to go.

 

[jeepguyOC]

I now have a 2006 LjR 6 speed on 37s and loved my stock 410 gears. Went to 488 and regret it every day.
I use to run a 2002 5 speed with 35s and 456s. I use to roll at 90mph @2700rpm and blew away my jk buddies rigs on the highway.

 

[PNW_LJ]

I now have a 2006 LjR 6 speed on 37s and loved my stock 410 gears. Went to 488 and regret it every day.

Did you regear to 3.73s by accident?

 

[machoheadgames]

I now have a 2006 LjR 6 speed on 37s and loved my stock 410 gears. Went to 488 and regret it every day.
I use to run a 2002 5 speed with 35s and 456s. I use to roll at 90mph @2700rpm and blew away my jk buddies rigs on the highway.

Something ain’t right, because your old Jeep on 35/4.56 would have been doing 3250 at 90. That and your experience with 4.88 is not typical at all - most would want 5.13 for 37’s with the 6 speed, definitely not 4.10.

 

[Jerry Bransford]

I now have a 2006 LjR 6 speed on 37s and loved my stock 410 gears. Went to 488 and regret it every day.
I use to run a 2002 5 speed with 35s and 456s. I use to roll at 90mph @2700rpm and blew away my jk buddies rigs on the highway.

None of that makes any sense.

 

[L J]

Something ain’t right, because your old Jeep on 35/4.56 would have been doing 3250 at 90. That and your experience with 4.88 is not typical at all - most would want 5.13 for 37’s with the 6 speed, definitely not 4.10.

None of that makes any sense.

He has a 241J transmission:

 

[machoheadgames]

He has a 241J transmission:

View attachment 451570

Ah, now I don’t see

 

[jjvw]

I now have a 2006 LjR 6 speed on 37s and loved my stock 410 gears. Went to 488 and regret it every day.
I use to run a 2002 5 speed with 35s and 456s. I use to roll at 90mph @2700rpm and blew away my jk buddies rigs on the highway.

This was your 2002...

AX15/33.875/4.56/3215rpm@90mph

And your 2006...

NSG370/35.75/4.10/2913rpm@90mph

and...

NSG370/35.75/4.88/3467rpm@90mph

 

[machoheadgames]

This was your 2002...

AX15/33.875/4.56/3215rpm@90mph

And your 2006...

NSG370/35.75/4.10/2913rpm@90mph

and...

NSG370/35.75/4.88/3467rpm@90mph

What would it be with 241J/35.75/4.88?

 

[jjvw]

What would it be with 241J/35.75/4.88?

Mine also has a 241J, so I don't understand the confusion on that one.

 

[machoheadgames]

Mine also has a 241J, so I don't understand the confusion on that one.
View attachment 451571

Lol - the past few posts contain the context. I assumed you saw them.

 

[jjvw]

Lol - the past few posts contain the context. I assumed you saw them.

I see now. People occasionally get incorrectly assertive about TJs having a 241OR.

 

[Rickyd]

What would it be with 241J/35.75/4.88?

241j transmission. Like a powerglide! 4:1 first and 1:1 final. But no syncros and a hell of a gear spread

 

[jeepguyOC]

BTW I don't drive 90 anymore. The AX15 and the NSG370 feel completely different. I also went from a Tj to an Lj. Thinking about it, I changed out the speedo gear in my 2002 I have not changed anything yet on my 06. I feel if I went with 4.56 gears now, I would be at about the same final gear rpm with the 2 different transmitions.
♧ My notes have my final 6th at 0.84
The Ax15 5th gear was 0.79.
Is the 231 vs 241J 2Hi gear different? I always have calculated both at 1:1.

 

[jjvw]

BTW I don't drive 90 anymore. The AX15 and the NSG370 feel completely different. I also went from a Tj to an Lj. Thinking about it, I changed out the speedo gear in my 2002 I have not changed anything yet on my 06. I feel if I went with 4.56 gears now, I would be at about the same final gear rpm with the 2 different transmitions.

We have more to go on than feelings. Did you see where I showed that you are making stuff up?

 

[machoheadgames]

BTW I don't drive 90 anymore. The AX15 and the NSG370 feel completely different. I also went from a Tj to an Lj. Thinking about it, I changed out the speedo gear in my 2002 I have not changed anything yet on my 06. I feel if I went with 4.56 gears now, I would be at about the same final gear rpm with the 2 different transmitions.

Maybe ya put the wrong speedo gear in on the 02 because again, those numbers aren’t even close to right.

 

[TJosh02]

My '02 5 speed has the NV3550 not the AX15. I am also on 35s and 4.56. 5th gear drops my rpms to 2300ish iirc at ~70mph

 

[jjvw]

My '02 5 speed has the NV3550 not the AX15. I am also on 35s and 4.56. 5th gear drops my rpms to 2300ish iirc at ~70mph

It does this...

NV3550/33.875/4.56/2470rpm@70mph

 

[TJosh02]

Sounds about right. Was going off of memory rather than math. Anyway, it makes 5th kind of not needed most of the time. It was geared for 33s originally and it isn't that big of a deal to bother regearing.

 

[jjvw]

Sounds about right. Was going off of memory rather than math. Anyway, it makes 5th kind of not needed most of the time. It was geared for 33s originally and it isn't that big of a deal to bother regearing.

Mine was the same setup with 4.88. It wasn't geared low enough for 35s. The plan was to go to 5.13 prior to the transmission swap.