Hey guys. Did some searching and I was only able to find sparse information. I tow a fairly larger boat, and would like to get some help on the larger hills. I currently have a 1997 F150 Lariat with 5.4L engine and a 3.55 axle with drum brakes. I want to swap in a larger gearing and convert to disc brakes to assist in towing. Can someone direct me tk what will fit? First thought is to look for an expedition with 4.10 gearing, but Im not sure if it fits, and what years I should look for. Thanks for the help in advance!

ATLBuckeye

 

You need to understand that disc brakes in place of Drums will result in the Brake bias being lost.
You will have to take measures to rebalance the front to rear bias.
Then there might be a matter of EMG brake hookup..
If not done right, you could end up worse than what you have now.
Speedometer won't register correctly with the gear change..
Good luck.

 

Thanks for the reply. Not familiar with the EMG terminology.

As for the bias, I wondered this as well. Maybe someone can chime in if I can pull the master cylinder from the same vehicle, if that would suffice.

 

emergency brake

 

Thanks. I dont have a clear solution for the emergency brake, but I have been told that it is mechanical as well, so I think it is a matter of reconnecting it for the correct tension, which may need some minor modifications.

 

A useful tidbit to know is that the Expedition's ABS Pump also functions as the Brake Proportioning Valve. So first you're aiming for N OE conversion, grab it and the rear disc setup from an Expedition.

Another bit to know is that it's a dual circuit setup, the front is independent from the rear. So if the front brakes goes out, the rear takes over in an emergency. I found this out firsthand when one of my lines broke, thankfully in a parking lot.

 

Good info. Thanks!

Do you know what years expeditions axles will fit? do you know of any thread or person that had made this swap to a 4.10, and disc brakes? If im the first person to attempt this, its likely a sign that I shouldnt be attempting it.

 

Last I checked, it was 97-02 Expys and 97-04 F150s that used the samd setup. It might go up to 09, but i'm not sure offhand. Check RockAuto on it

 

Cant seam to find evidence on RockAuto of the 4.10 setup. Any insight?

 

I thought the Expeditions had IRS ?

 

You would know better than I would, experience has that benefit lol. As for 4.10 gears, I would imagine all Ford 8.8 rear ends use parts from the same pool and can be swapped around accordingly. Mazda is like that with theirs, in that you can swap a RX7's diff gears & LSD into a MIata, B-series pickup (or Ranger ), or any rwd 626 as they all use the 7" ring gear

Perhaps check an Explorer or Mustang?

 

OOOOOOOOPS... I misspoke. The Expedition is not IRS, but it does have coil springs instead of leaf... Axle housing is not interchangeable with the F150, but I agree internal parts for the 8.8 are "normally" similar just as the 9.75 parts would be interchangeable in the larger housing ( but different cases).

 

So is my only option to pull an F150 that has disc brakes and a 4.10? Does that exist? What about explorer? I wasnt sure if it had the correct wheel base.

 

explorer is a much smaller truck... and those built after 2002 have IRS rear ends which wont work........ but they are 8.8 inch so internals could be usable.

 

disc brake conversion is probably not economical on a 20 year old truck.. You could buy a 4.10 gear set and have that installed and get your pulling load up.... I assume this is a 2 x 4 truck and no front axle gearing is needed ?