Diffs: re-gearing & lockers

[The Beard]

While I can't speak from experience, there is a view that 5.13's in a Dana30 is a bad idea. As you lower the ratio of the R&P, the teeth on the pinion get smaller and weaker, making them more prone to stripping. The 5.13 pinion in a Dana30 is very small because of the size limitations of the pumpkin.

Given you said you're unlikely to go to 35's, and you're already running 4.1's why regear at all?

If you think 35's are likely in the future, I'd go the 4.88's.

[wheeler33]

Originally Posted by The Beard

Given you said you're unlikely to go to 35's, and you're already running 4.1's why regear at all?



If you think 35's are likely in the future, I'd go the 4.88's.

Think of it like getting a boob job, might as well get an ass job too!

I don't mind what it's at right now, it drives okay and it'll potentially save me $ towards install or something more useful.

Thanks for the advice


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[Rodent]

hhmmmm, boobs.

[yetiboy01]

Originally Posted by Johnboy

Yetiboy is yours auto or manual? Sport or Rubicon?

auto sport

[Johnboy]

Im about to regear to 4.88 in my manual Rubi Unlimited as 4.11 on 35's is a real mismatch as i spend most of my time in 3rd and never use 6th even on the freeway. My only concern was 4lo being to low in the sand but i guess starting in 4th isn't the end of the world. Hopefully I'll be able to roll 4hi once the gearing is back where it should be.

[yeahright]

Mate, I have an 07 sport, auto with 4.88s and 35x12.5x17 Coopers,
If I had a d44 in the front I would have gone 5.13 BUT the pinion in a d30 is way too small, and it would rev like hell on your 33s,
My car sits on 2000rpm at 100ks and 2200rpm at 110ks,
NOW the only reason for wanting 5.13s was I was going to get 37s but the risk with the fun police was too high.
I have a mate with 4.56s in his 2011, 3.8, sport, auto and he regretted not getting 4.88s.
My car will occasionally still hunt for gears on some hills but not like before regearing.

[Jakstas]

i have a 09 JKU with the 3.8L and 4 speed auto.
running 285/75R17 km2s
with 4.88 diffs
gets about 15-17L per 100kms on the highway depending on how hard i drive.
sits at about 2300rpm at 100kms a hr.
its been like this for 60 000kms so far. gets expensive quick.
ive been told if i put 35s on the fuel economy might get better. i haven't tried yet though.
the dana 30 is all sleeved and gusset with chomoly axels, so next set of tires i probably will get onto that