So, long story short: I was redoing the rear brakes on my 1986 F250 LD and noticed that the axle-shaft bearings and seals were shot (had almost 2 inches of play)

I'm wondering how difficult it is to replace the bearings and seals in this axle (sterling 10.25 semi-float). I've got a 1990 F250 HD that has the full-float 10.25 in my yard, and I could rob the axle from it if it would be easier just to swap the axles.

I'm fairly novice when it comes to mechanic work, and I have very few specialty tools. But I'm willing to try and learn from experience, just wanted opinions on which way to go with it.

 

Semi-floating bearings aren't that bad to replace, but if your F250 is a parts truck I'd swap axles. But the main reason I'd do that is because I prefer full floating axles.

 

You will have to take it to a shop to have the bearings changed. I haven't changed the bearings on your particular axle, but have done many others and they have a retainer that is usually split and or pressed off, and then the bearings are pressed off and the new ones are pressed back on. Then the retainer on both sides.

Not difficult, but if you don't have a press, you have to hire someone to do it.

 

What you are thinking of is unique to a 9" and other semi float axles without Cclips. The bearing and seal are both sitting in the end of the housing and the axle slides right out on his truck. The bearing is easiest done with a slide hammer.
However, if the bearings are that bad I would expect to find damaged shafts, in which case I would swap the full floater over. But I would check them first.

 

The 90 F250 started out as a project, but with the time and money I've been spending on the 86 I've just about decided to rob the parts I like off the 90 (rear axle, 460, and maybe the Dana 50 TTB) and scrap the rest as it is going to require more work than I'll be able to do to it in the foreseeable future.

Only issue I know of is that the 90 axle will probably need new brakes and a coat of paint, as the truck was used for launching boats into the Gulf and is quite a rust bucket.

As it stands right now, I'm going to try and fix the current axle in the 86. If it looks like it will be too damaged, I'll swap in the full float. Otherwise, I'll probably pull the full float from the 90 soon anyway and go through it so I'll have a spare.

 

Thanks for the info. So it's like the 8.8's where the bearing rides directly on the axle shaft?

 

Yes, the sf 10.25 is just like the 8.8.

 

You are likely going to need axle shafts along with bearings and seals. Unless the 90 full floater is really rusted, I would swap it out in a heartbeat. The brake shoes, springs wheel cylinders, e-brake cables and seals are cheap compared to replacing axle shafts.

I just replaced all brake parts listed above on my 86 F250 diesel for less than $100.

Also had to replace axle shafts, bearings seals and all brake hardware on a 93 F150 with an 8.8. It was nearly $300 for everything.

 

Yeah, I priced axle shafts for the semi-float. I'm looking at $200 per side if I have to replace them. The full float axle is looking better and better.