Yukon Grizzly or Detroit and other ?s

[Desert Thrasher]

So I pulled apart my rear axle today to change the pinion seal and housing gasket, only to discover that my old stock 28 spline axles are twisted. So now is the time to upgrade. I wont spend money on an aftermarket set of 28 spline, even though I know it is the cheapest and easiest route. I am thinking of going with 35 spline axles and either a Detroit or Yukon Grizzly locker.
Who has the Grizzly locker and what do you think of it? I currently have a Detroit and its great. But the Grizzly is cheaper, and I am wondering if it is as good as a Detroit or better or what?

For gear ratio I am thinking of 5.13's. Currently have 4.56's, but since swapping the ZF 5spd in, I think a lower ratio would be better. I currently have 35" tires and plan for 37's when the 35's finally wear out. Bronco is mainly offroad, but I do drive to the trails, sometimes over an hour one way.
Anyone run 5.13's? What do you think of them? Too low or would be fine? I have played with the calculators and think this is the way to go, but it would be nice to get others opinions.

Thanks.

 

[AZ69EB]

The 35 Spline swap cost a lot more compared to swapping in 28 or even 31 Spline axles.
You will also have to take into account the additional cost of 35 spline axles, new third member, new pinion support, new bearing kit, and 35spline locker.

I was fortunate, as I have been stockpiling parts for over a year. I also won a Yukon large bearing nodular 3rd member at the AZ Bronco Stampede. Then I found a new in the box 35 spline Detroit at a price I couldn't pass up.

I also just swapped in the ZF and added Ford EFI on my 5.0. I was running 3.50 gears until I broke my 9” housing a few weeks back. This pushed forward the gear change and a new Currie heavy duty 9” to the mix as an additional parts upgrade.

I’m going with 4:88’s with 33” tires. I will up graded to 35” tires when these wear out.

I still wanted to be able to drive it down the highway at a decent RPM with either 33” or 35” tires.

FYI – Wildhorses has a 35 Spline Detroit in the classified section for sell at a reasonable price.


Good luck.

 

[Amac70]

I just got a new arb's and 5.13's last week. im thinking that is the right combo for 35-37 with the od(i swaped out the zf for a 4r70w) You can get the nascar detroits off ebay for 249 they work well, they are just loud that is pretty much the only reason im ditching mine, tired of hearing it all the time. I would stick with the 31 splines. Where i buy my stuff the axle prices are the same its just the cost of upgradeing everything else that get really expensive.

 

[Apogee]

I went back and forth between 4.88's and 5.13's and ultimately went with the 4.88's for a couple of reasons. I run a relatively mild 351W, so the torque is respectable, moving my cruise RPM down. I have a NV4500 waiting to go in at the same time as the gears and 37's, so it should be somewhat similar to your setup with a ZF.

The primary two things that made me choose the 4.88's over the 5.13's were that they're weaker than 4.88's and they tended to put me right at my shift points for 3rd and 4th gear where I normally cruise for speed limits. I can't find my gear ratio spread sheet at the moment, but I spend a lot of time at 35, 45, and 55 mph give or take and I'd rather be in the middle of the powerband, not top or bottom of the gear for driveability's sake.

 

[JakeAlex]

I went with griz full lockers from and rear. Also upgraded to 31 spline rear axles and 4.88s. So far I mainly use mine on the roads and this combo with 36the irocs have been great.

Only thing id do differently is I would go with an ARB in the front. Other than that I've been very pleased.

 

[Desert Thrasher]

So far Im liking what I have been reading on the Grizzly. I am thinking of just buying a complete 3rd member dropout from JBG. So far they have the best price I can find. Anyone know of better prices? What does a good used 3rd member dropout with a 28 spline Detroit and 4.56s go for?

Amac, why 31 splines instead of 35?

 

[Desert Thrasher]

hmmm well I think I answered my own question concerning 31 or 35 spline axles. About $300 more for the 35 spline 3rd member dropout. So 31 spline Moser axles, opnions please? How much abuse can they take?

 

[Oatmeal]

You, know there is a much cheaper route you could go.

I used to have 28 spline shafts with a Detroit (Soft Locker) well, after breaking 3 (yes 3!) Dutchman alloy shafts (don't even get me started on those clowns......never broke a stock shaft), I bought a Warn full floater kit when they first came out about 14(?) years ago and of course, I needed a 31 spline locker.

I was able to buy a pair of 31 spline side gears (drivers) and converted my 28 spline Detroit to a 31 spline for alot less money.

I got the parts through my local off road shop but:
http://www.stockcarproducts.com/rear2a.htm

Prices have gone up but, still cheaper than buying a new locker and I'm sure you could get them cheaper somewhere, I only paid around $50 for the pair way back when.

IIRC, if going to 35 spline shafts, you'll need a new third member because, the 35 spline lockers have a bigger axle shaft bore that'll require bigger carrier bearings thus, the need for a new third.....I think?:?

Hans

 

[ryan287]

I have 4.88's, 35's, and an NV 4500. Sort of wish I would've gone with 4.67's from Currie or 4.56's. Around town I end up rowing through gears quite a bit. I have 31 spline axles and have had no problems through many burn outs. I would suggest putting the extra money in a D20 high output shaft from WH's and better U joints. I have broken both original parts from stress and those are expensive fixes when you're moving.