Dex1

On the last post on 4 LO most everybody was running manual trannies... I have an auto and have used 4 LO on the trails but I am goin to be running on very soft, very big sand dunes this weekend, and from what I have been told you need alot of momentum to summit some of the larger dunes, would'nt 4 HI be a better place with an auto trans for soft sand and or snow???

voodoojk

yes as long as your engine can spin the tires. With my 35's, 4 high is worthless on any off road situations. i just dont have the gear to turn the tires. You want 4 high and turn off traction controll.

goldtr8

It depends, if you have a Rubi with a 4 to 1 ration 4 lo may be tool low in the sand.

If you have an X that a different story.

Its all about gear ration and a big contact patch.

For sand I run the stock rubi tires at between 8 and 10 psi and now I dont get stuck in the sand anymore.

scottrock

Don't need momentum as much as you need a large contact patch. Also the comment about gears is correct. Air down and give it a go in 4H, if the rig seems to struggle, hit 4L and a higher gear. 4H can actually put more stress on the drivetrain due to the gear reduction you get with 4L.

Dex1

I have a rubi, 2 door, auto w/ 3" lift and 35's, I have not put gears in it YET, so I will be under the gun for sure...

scottrock

IMO in that light, I'd run 4L and air em way down.

Dex1

Thanks.... I'll give it a shot!

tkob1060

with the 4:1 rubi case and auto it will also depend on how long the hill is, a longer hill you will DEFINITELY need 4hi or you will tack out and loose all momentum.

WranglerDan

+1 on the tire pressures in sand. The softer it is, the lower you need to air down. And take a shovel.

slangheld

I know this is an old post, but for the sake of those doing a search, here goes. I learned most of this less than a month after my used purchase and 15-20 minutes after hitting the beach. I have an 09 JKU automatic, so some of this wont apply to manuals. After much research it seems the general consensus is to air down to 15-20 psi as a starting point. I would say the posts above agree with that. Use 4L. '07-'11 auto's will overheat in 4H unless travelling 25-30 mph. Related to that, get an auxillary transmission cooler. The stock cooler is mounted to the a/c condenser and is tucked behind a cross-member and the front bumper. It is undersized and gets almost zero airflow. You can also turn your a/c on to force the cooling fan to come on. I believe 4L automatically turns ESP off, so that's covered. Also, turn O/D off. More than a little late to help the original question, but hopefully useful info to others. You can find more related info by searching this and other forums for "hot oil".