Pluke the 2

It's not the slipping. It's the low gear's trying to maintain speed...

Pape

gears trying to maintain speed ?? you will have to explain the big picture here

for automatic trany limiting the torque converter work is your best way to control the heat in the trany

dustinc83

very good then.. i guess i dont have to regear then. just pop it into 4low when need be!!! thanx guys

tslewisz

HAHA! Gotcha. I had 3.21's and changed to 5.13's. Wonderful...

dustinc83

Do the gears in the transfer case have anything to with the gears in the axle when in 4low????

GoodysGotaCuda

They all add up to a total 'crawl ratio'. Transfer case ratio is separate than the axles. 4:1 case with 3.21s or 4.10s are two different animals.

GoodysGotaCuda

Just depends on situations. Rock crawling primarily relies on very slow and fairly accurate adjustments of the rig. Which can be difficult without low ratios (much much lower than a 3.21 axle and 3:1? case). If you aren't on the rocks, or hanging tires on obstacles, you'll be alright!

Pluke the 2

4lo actually puts more stress on the running gear as it converts speed into torque.

Pape

Well I scratched my head for a couple of minutes here and came to conclusion from my understanding of gearing and how radio affect the number of turn and such that your assumption will be true only if the transfer case was before the transmission in the drive line. Unfortunately the drive line on a automatic Jeep is as fallow :
engine -> torque converter -> transmission -> transfer case -> axel gearing -> wheels

When you go in 4 L the transfer case and axel gearing will see a increase in applied torque not the transmission, torque converter and engine. The transfer case serve 3 functions on a Jeep: first it transfer power to the back wheels, second it transfer power to the front wheels and third it act as a second transmission offering 2 gear ration H 1 input turn for 1 output turn and L (rubi) 4 input turn for 1 output turn.

Here some ratio mathematic based on first gear 2.83:1 and rubi spec (for Sahara and X replace transfer case for 2.71 and auto axel 3.73. Note torque converter is set to 1:1 even if it impossible in first gear as I don't have a clue how to calculate it properly, but if any one can shine in and give us the math will be greatly appreciated)
use: engine -> transmission -> transfer case -> wheels

2/4 H example:
1500 -> 1500 / 2.83 -> 1:1 -> 530/4.1 -> 129 turns at the wheels

4 L example:
1500 -> 1500 / 2.83 -> 530 / 4 -> 133 / 4.1 -> 32 turns at the wheels

Since I don't need speed most of the time on the trail but torque for overcoming obstacle without the need to ram it I use 4L. Also I observed for equal speed the higher gears look to be keeping the transmission cooler as I think the transmission pump is running out of the output revolution of the transmission but do not have any proof.

ronjenx

It has been my experience that going into 4lo reduces the automatic transmission temperature. I can watch it on the gauge.

In 4hi, on the trail, the tranny may not come out of 1st or 2nd, therefore the torque converter never has the opportunity to lock up.

Being in 4lo allows the tranny to make it to 3rd, and if you have the O/D off, the torque converter can lock up, at least some of the time.
I can see the temps go up in 4hi, and go down in 4lo.

Also, most of the time, turning on the A/C will reduce temps a little more.