Roughly three years ago I spent the first real money on my truck in a decade for a used engine and 3 inch lift, then I added a couple of more inches. Then pucks, then tires. Except for the engine, it was all for looks. After a bumper, winch and 20000 miles, I am at about 3.5 to 3.75 over stock on MD springs. I have 33 inch tires (and I doubt I'd ever go bigger) and wheel spacers. The tires are heavy. Stock wheels. HD front shaft. Everything else stock except the obvious (brake lines, shocks, etc.). If I made any change in tires when these wear out I'd go a little smaller to save my fenders.

I didn't destroy anything with lower gears because, well, I'm a very slow driver.

When I was learning about the lifts and tires one of the things everyone said was that I would need caster correction, gears, and HD shafts. That's all correct. I've muddled along without caster correction because I'm going to be getting HD springs and the lift may change--i just got used to the twtichy steering. But I like the 33's and have been spending some serious money on my truck lately (several thousand... I consider that serious money), and gears is next on the list. Lockers will be after that.

So, what I have read for gears is that 4.11 is about right to return to stock RPMS (over th stock 3.54 ratio) with 33 inch tires. I have also read that GBR makes good ones. Anyone who has read my posts knows that I'm not afraid to try anything, not a mechanic, I try everything, and it usually but not always works out. However, I have NEVER seen the inside of a differential.

So here are my questions:

1. With 33 inch tires is 4.11 about right for return to stock? I drive highway a lot, so I don't want to make crazy RPMs at 75mph. But I've also invested a lot in a 4.6 engine and I would like to feel the difference.

2. Is GBR the place to get them? Are there any options on gears that I need to know about? Any sales anywhere?

3. Anything I really HAVE to replace with the gears, such as axleshafts or CV joints?

4. Can an idiot do the swap with guidance or does this really have to be done at a shop? Any special tools? Are there any gotchas in the process?

5. I've read all there is to read about lockers and it sounds like truetrac front and back is what I will need (though I am open to trusted opinions!). Looking ahead, what's a good place to get them and should I put them in at the same time?

Thanks!

 

5. If you're thinking about lockers (or TT), do them at the same time, that way you don't have to have them set twice.

2. Yes, GBR.

1. Ashcroft has a calculator on there website. You can mess around with all the ratio's and come up with the best solution for what you are after.
Ashcroft Transmissions - Ratio Calculator

4. If you buy from GBR they should be set. Slide out 1/2 shafts, remove drive shaft, unbolt third.. then reverse it.

3. don't think so.. i believe you said you had HD axles... queue up the HD axle debate.

 

If you're doing R&P's you might want to consider a higher R&P ratio and then also change your transfer case gearing to keep a good high range overall ratio, but allow the R&P's give you a higher overall low range ratio for slow speed driving.
It really depends on the type of terrain you off-road in.

 

I don't off-road at all in my rover, other than sand and gravel roads and curbs. My offloading experience is in modified ATVs. But the plan is to take a trip to the kiamichi trail in Oklahoma and Arkansas late fall. It ranges from class 1 to class 4. People used to do it in stock vehicles with lifts and tires. From what I have read and seen, there are now some areas where having two tires off the ground is possible, and where rock ledges on hills with loose rock up to about ten inches have to be traversed. If that's any help. I figure if ican do those things I'll be able to do anything I am likely to try in the future. If that helps.

 

I do have an HD front but the budget and plan is for TW multi double cardan in front and double cardan back with u joint in the rear.

Really, no matter what I do iIneed to preserve road manners.

 

I run 33" on 4.11 with a TT front and D Lockers on rear. You really don't need anything except CDL for the Kiamichi trail. If you are planning on running harder trails I would recommend TT front and TT rear, or TT front and D Locker on rear. Re-gearing to 4.11 is recommended if you are planning on wheeling extensively in higher altitude with 6% or higher grade and only if you are driving it in the highway. Else you won't have enough power to pass someone or keep up with the speed limit. If you are trailering it, the current gear ratio you have is fine unless your into hard core rock crawling.

 

Dwv, did the 4.11's return you to stock RPMs/acceleration?

 

you dont want to do a ring and pinion and then install a locker, it twice the work.

 

It is also twice the money or more but I take your point. Dro, do you have lockers and, if so, mind telling me what setup you use and why? I don't have anyone local to bounce the gears and lockers questions off of.

 

I run a stock 30-31 tire so there is no need.
With a 33 you need to go to a 411 to get your lower end back.
With a 33 and a locker you probably need to upgrade they axle shafts that's a lot of grip.
if your not climbing rocks your traction control should suffice, in most cases.
GRB is one of the best if you have to have the best.