I am wanting to swap my 8.8 for a 9.75 in my 95 f150 4.9 with 5speed od. I pull a trailer allot and I am going to fry this disposable 8.8 with a lousy 2.73.

dose anyone know if there is a year and model of truck that would have one that would be a ez swap?

 

97+ 5.4 at earliest. One problem I see is that the 9.75 only came with a 5x130mm, 7x150mm and 6x whatever the '04+ are, metric lug patterns. Not the 5x5.5" like ya have now, and would need two spare tires.

Adrianspeeder

 

I considered that swap for the extra capacity & rear disk brakes, but I haven't found a good axle at a good price yet. In addition to the lug spacing, you also have to consider that the shock mounts & spring perches are wrong for our older trucks, so they'd have to be cut off & welded back on to mount the axle.

 

how about the width? would it be close? I can get one of those pretty cheep down here in Mexico, and the fab work is cheep here also.

what Axel did Ford use for towing in 95-96, they must have had something heaver than the 8.8. maybe a 9 inch?

 

Nope, 8.8 semi float replaced the 9" for the half tons from '85ish depending on engine, and still used with the 4.2 and 4.6L

From the same time on F-250s got a semi or full float 10.25 depending on GVWR, F-350 SRW got a full float 10.25, '99+ Superduty SRW have the 10.5, 84+ duallys have the Dana 80.

I'll get the widths from my buddy who works in the ford axle plant.

Adrianspeeder

 

so I guess my only option is to go with the 9.75 and make the mods. I can get one here for 200 dollars and get the mods for about 50 more. the same donor truck has a ZF transmission that I can get for 250 more with the clutch flywheel drive shaft and the whole ball of wax. so I think I will go ahead ad get it and then figure out how to fit it in there. it is nice to be in Mexico when doing these kind of projects because you can do every thing so inexpensively. I now in the USA they want over 1000 bucks for a ZF used.

 

FWIW,....

The 8.8 rears can handle anything you can throw at them if you put good parts in them.

They come stock w/ 31 spline axles (which I've never seen anyone break yet)

Just install whatever ratio Ring & Pinion you want (preferably Ford Racing gears), weld the axle tubes to the diff. case and install a Detroit Locker. You won't break it,...... I'll bet money on it.

I use an 8.8" set up just like this in my Lightning and have had great results.
My truck is making 700+ to the wheels in conjunction with a trans-brake.

I'm not alone either. There's several of my racing buddies that's still using 8.8 rears and making much more power than me and no problems.

 

You mean ZF?

Don't know of any truck sold with the ZF 9.75 combo. What is the donor?

Adrianspeeder

 

the thing is I am not racing or just driving this truck on the street, I am pulling a heavy trailer up and down Baja and it just puts to much strain on it. it gets very hot and I change the grease very often because it burns the grease. I am sure if I was just running it down a 1/4 mile strip it would be just fine. but it is 40 hours of hard driving on bad rodes to get from one end of Baja to the other and few places to get any sort of help when something brakes. this is a good truck for what I am doing, the only week link is the rear axle and the transmission. and I would like to Beef them up a little. I know a lot of folks would say why don't I just use a F 250 or F350 and the reason why is the suspension is just to stiff and you beat your self and your truck to death. all I need is a pulling machine that can stand up to the torque of the 4.9 for forty hours strait time after time.

Chevys dont last long down here and jap junk is a joke. Ford rules in Baja

 

it is a 2002 F250 but some one had changed the transmission and maybe the axle also. the truck caught fire and burned everything from the trany forward. just another Baja casualty

 

here is an interesting link to a site I found I found

http://www.drivetrain.com/ford9.75.html

 

Why not source a 9" out of an older Ford?
Seems perfectly reasonable to me, and they are tough.
Not that the 8.8" isn't strong... but if you want really strong and bolt-in, that would be my choice.
Dave

 

He needs the tone ring to operate the speedo/odo and the RABS. A 9" won't work.

 

yes I need the tone ring. It seem that the axle flanges can be redrilled to fit the older stile none metric ford rims. I don't know what kind of trouble I will have changing over to the disk brakes. what about the emergency brake?

 

A 9" is no stronger than an 8.8", and weaker in some ways.

You could drill the axleshaft hub flanges to mount older 15" rims, but they won't fit over the brakes. You have to have 16" rims.

If you keep the stock brakes on the new axle, it has the e-brake built in. You just have to connect your cables to it. That's the hardest part of swapping the brakes (disk OR drum).