I've been thinking about getting some Locker (I have ford's junk Limited Slip now) and re gearing to something above 3.73. I have 37 inch tires and want to get back some of the MPG and performance as when I had my stock tires. Has anyone done this and what brand of gears/locker are good.

I went from 235/85R16 to 37x18, would someone recommend the new gear ratio to get me back to stock final revolution, Thanks.

What Lockers work good with out trashing the tires when turning? I am assuming that the rear axel is the only side that gets Lockers while the front stays locker-less.

Thanks in advance

Dave..

 

235/85R16 have about a 99.6" circumference compared to the 116.18" circumference of the 37's. That means that your original tires roll 85% of the distance per revolution that the 37's do. To correct for tire height you would want about 4.35 ratio. I do no know what ratios are available for our axles. I have never done gear work on my truck but I did regear my Jeep. As for lockers I really do not know which lockers are best for our trucks. I have a You can also look at selectable lockers like the eaton E-locker, ARB air loacker, or the OX mechanically selectable. So called "lunchbox lockers are nice because they do not replace the carrier.

 

I would look for OEM, Spicer or Yukons IMO in the gear selection department. Both have been proven to be quieter, and more durable. As far as lockers go, it depends what you want to do. If you want to have better traction offroad, and not compromise onroad, I would look into ARB selectable lockers. If you want max traction, and dont mind the extra tire wear, get a detroit locker (my personal favorite) If you want better onroad and offroad performance, with less tire wear then the detroit, i would look at an eaton posi, or a torsen differential. Caution on the torsens, you need to learn how to use them before you go out and get one and bash it for not working. Eaton posi units are available for the sterling rears, and IMO are about as good as it gets as a limited slip unit. They are fully rebuildable, and IIRC can be adjusted tighter or looser with different springs. They are really durable units too. In the front, if you want anything youll want a selectable locker. Anyone that has used a front locker in off camber/sidehills with ice, snow or slippy anything will tell you they can cause as much trouble as they fix. Hope that helps. I just love my detroit though.......

 

Since having to go into the differentials and pulling the axles, what else is needing to be checked? Front hubs? Axle barings? front U-joints (rear have been changed), Etc... I do not want to have to go back in to do something else.

For the Lockers, I am just wanting something better than the Limited Slip I have since it does not really work. Who makes a limited slip diff that really works?

Dave

 

detroit truetracs are nice along with the 4.56's, a little more grunt for those 37's to play with.

 

This is simple and straight to the point. The 4:56's are what everyone around here are using with that size tire. The True Trac is hard to beat for the price and is very streetable. I have the Detroit Locker in the rear and the True trac in the front.

 

I also recommend the 4.56's.... 4.30s won't quite get you back to stock plus they are heavier which means you won't be at stock. I have 35's and i want to get 4.56's so i am comparable to a dually with 4.10s on stock tires.

 

Dave, check with Ron at HMP, I am sure he has a good deal on gears.
get his comments on what lockers/posi he would install/recomend.
let me know when you are going to have it installed!
good luck!

 

What gears Manufacturers are good, which ones should I stay away from? These are some that I have found..

Accu Gear (4.56)
Motive Gear (4.30/4.56)
Precision Gear (4.30/4.56)
Spicer/Dana Gear (4.30)
Yukon Gear (4.30/4.56)

4.30 will get me back to stock final drive ratio. (tire calc said I needed a 4.34)

What would keep me from buying a 4.30 gear verses a 4.56. Which is stonger/weaker

I still want to get good mileage on the freeway.

I believe I have a Dana 50 in front and Sterling 10.5" in the rear. I have 3.73 ratio in the differentials.

Dave

 

Personally I'd to the 4.30s with 37s.


I run 4.56s with my 38/15.50R20s (ran 40/15.50R20s with them as well).


And yep, you have a D50 and the Ford/Sterling/Visteon 10.5" rear.


You just need the gear sets and the master install kits.


For the limited slip a Trutrac or a ARB is a nice selectable locker.
I run ARBs front and rear.

 

What Chi-town Suburb are you in?

I'm in Lake County close to the WI border (right by Fox Lake).

 

Dana/Spicer and yukons are my favs, first choice being dana spicers....

 

I live out in Naperville...

Dave

 

How many RPMs will you turn on 4.56s @ 65mph, with 35 in tires, when these 37in toyos of mine are done im going back to 35s. Have thought about regearing but my concern isnt around town mileage, more the highway it seems like you would be well above 2000rpms @ 65-70mph???

 

Link to a chart I made that shows RPMs at 70 mph with different tires and different gears:

http://www.FTEs diesel forums.com/fo...ead.php?t=2896


With a PSD and 35s, I personally wouldn't regear unless you tow heavy and need the gears. If you don't tow, I'd just stick with the 3.73s