5.13 or 5.38

[Pokeman]

what would be a better choice. 60 front, Sterling rear, running 39.5's on yj. 4.0.

I am in the east, I avoid the mud holes more into trail riding and climbing. Wheel speed is important on the slick hills. I am currently on 35's with 4.10 and I go a bit too fast on the rocky trails and creek beds for my liking but need 2nd on the steeper/slicker hill climbs. I would like to slow it down a bit for trail riding, and use 2nd & sometimes 3rd for hills.

what say you?

[ONEtonXJ]

i say run a 231/300 doubler...

-stronger, bigger pinion... now i realize it's a 60 and lower gears are not an issue....... but, bigger is stronger..
also, the 300 is a WAY better case for 4wheelin.. gear driven case, no chain.. cast case vs aluminum case = stronger....

-cheaper, you're going to have to change carriers to go 4.56 or lower, there goes 100 bucks or even more if you want a locker... then the gears are a little over 300 bucks.. then another 100+ bucks for an install kit... your already at 500 bucks for just the front axle..

-lower, 5.13s will only give you a 78.14:1 crawl ratio, assuming you have an AW4... If you keep the 4.10s and do the doubler you'll be at 163.62:1!!!!! OVER TWICE AS LOW!!!! now i know your lookin for wheel speed as well which isn't a problem.... shift gears...
if you have an AX15.. your crawl ratio will be 111.90:1

-packaging, a 231/300 doubler is SLIGHTLY bigger than the stock 231 case so fitting it in there is not a problem...


-price, i paid 100 for my 300, 100 to rebuild it, 515 for a D&D machine doubler kit... signed sealed delivered, done...


took me a weekend to rebuild the case and build the doubler..

[Pokeman]

the tons I am building off from have 3.54 gears in them currently.

my current set up is dana 30 & 8.8 with 4.10's. its all getting ripped out.

i won't pretend to understand the crawl ratio. I don't know what is ideal. so please bear with me a sec on this....

Would it be possible to keep the 3.54 + run a doubler and still have a better crawl ratio than I have on 35's with 4.10?

The pricing on the gears is giving me heartburn. 2 install kits + 2 sets of gears + 1 Detroit = $$$$

[JesseA]

running 3.54s and a doubler will make you hate life. you will chew up Drivelines, transmounts engine mounts ect.
Toyota guys have this problem when running duals, 4.10s big tire and a 4 banger.

Id go to 5.38s myself.

[ONEtonXJ]

yeah if you ran the 3.54s you would only be able to run in low or double low... double high would work but it'd get super shitty mileage...

it wouldn't break shit though.... it'd break less shit actually.. high gears less power...

crawl ratio is just the lowest possible gears your rig is capable of.... i run 40s with a GM 60 front 70HD rear with 4.10s in both and that doubler set up... my rig is also trail ONLY.....