I believe that I have a 10.25 semi <a href="http://www.motorhaven.com/">float</a>er in my '86 f250. I've heard that this is a really good diff. for off-roading and towing, but my question is.... Most likely, what is the gearing on this puppy? I have pretty quick take off when I mash the pedal so I figured it was about 4:10 or so. Maybe not. Also, this is a Limited Slip right? I'm not sure if I like that or not. I kinda like the idea of both wheel turning at once... Questions, comments, smart-*** remarks... I welcome them all, so let me hear'em.
Thanks,
Cameron

 

i dont believe that they made a semi <a href="http://www.motorhaven.com/">float</a>er sterling 10.25" rearend. they are only full <a href="http://www.motorhaven.com/">float</a>ers. if you have something that sticks through the center of your rear wheels then you have a full <a href="http://www.motorhaven.com/">float</a>er rearend. in my 84 i have a dana 60 semi <a href="http://www.motorhaven.com/">float</a>er. to find out whats in your rearend, we need your axle code on the drivers door and to tell what gears and if you have l/s you need to lok for a tag bolted to the cover on your rearend.

 

Yeah, they made a semi-<a href="http://www.motorhaven.com/">float</a> 10.25. I'm about to replace the one in my '90 F250. Gearing should be either a 3.55:1, 3.73:1, or 4.10:1. For an '86, you more than likely have a semi-<a href="http://www.motorhaven.com/">float</a> Dana 60. Look around the top of the pumpkin. If it has a "60" casted into it, its a Dana rear. A full-<a href="http://www.motorhaven.com/">float</a> rear has a huge hub sticking through the center of the rim. Semi-<a href="http://www.motorhaven.com/">float</a>s are flush with the back of the rim, like on 1/2 or smaller trucks.

Side Note: Semi-<a href="http://www.motorhaven.com/">float</a>s make LOUSY off-road rearends. The entire axle shaft is held in place by a C-clip. Break the clip, out comes the shaft with your tire still in place.

Stryder

 

From what you've described, now I'm almost sure that I have the 10.25 semi-<a href="http://www.motorhaven.com/">float</a>er. It's flush on the hubs. Oh, and the axle code said 29. I'll look for the #'s on the tag later on. but for now i'll say it has 4:10 gears. What's this rear end good for if it's not good for off roading? Towing? Is it possible to convert this rear so that both wheels turn simultaneously? I guess that's called locked. Thanks again.

 

Ya'll got me thinking.....can someone take a picture of the axle flange next time you've got a wheel off...i'm wondering if theres room to redrill to a 5 on 5.5 bolt pattern...see i wanna use a sterling with my half ton wheels....

THanks guys

 

its good for converting to a full <a href="http://www.motorhaven.com/">float</a>er. I have the same rear in my 2000 f150. While its a mega beefy rear, its kinda unlucky to have it. But you either get the 10.25 or 9.75 with the 5.4 so i guess it sucks either way. The 8.8 has way more aftermarket options, as does the 10.25 full <a href="http://www.motorhaven.com/">float</a>.


You have two options for positive traction on a semi 1/4. Lock Right Locker or Ford Trac Lock. They both have trade offs. The lock right is a little harsh on the road, but its locking ability is great. It will turn both wheels when you need it. The Trac Lock is a clutch type limited slip that isn't very agressive. It is far smoother than the Lock Right, and will probably do ok for what you want. If you regularly go off pavement, the lock right may give you better service than ith as me.

I think the best option is the detroit locker. however, they aren't available for the semi 1/4 axle. Only the full 1/4. They have better unlocking abilities and are the strongest carrier you can get. They are also alot quiter than the Lock right, but more expensive and more involved to install, but still not bad.

Chris

 

My truck is normally a pavement pounder, an only a 2wd. But I'd like to think that I can still dive into the rocks and goop with the best of'em. In other words I need a rear that will be good off road and better on. and I have to do it w/in the realms of cost and labor. So in that case what's the best choice? I can only deal with options for the semi-<a href="http://www.motorhaven.com/">float</a>; since that's what I got. And keep in mind its an '86 F250. (I run 33s with 15x10 Steelies if that makes a difference.)

 

Axle code 29 make it a 3.55:1 ratio.
https://www.ford-trucks.com/articles/axlechart.php
I may be corrected on this, but it was my understanding that you couldnt convert a semi to a full <a href="http://www.motorhaven.com/"><a href="http://www.motorhaven.com/">float</a></a>. Your best bet for a strong rear is to get a full <a href="http://www.motorhaven.com/"><a href="http://www.motorhaven.com/">float</a></a>. It will give you the reliability your looking for. The 10.25 is a STOUT rear for towing, but it suck once you start putting off camber pressure on the rear tires. I'd look for a full dana 60 or a full 10.25 in the local bone yards. You might even get lucky as I did with a wrecking company that has a bunch of junkers. I got a complete 460EFI F350 2WD with a 4.10 full-<a href="http://www.motorhaven.com/"><a href="http://www.motorhaven.com/">float</a></a> Sterling for $75!

Stryder