What's new

10.5 swap into an OBS/disc brakes

Tiha

Red Skull Member
Joined
May 20, 2020
Member Number
711
Messages
889
Has anyone done this?

I would like to swap the 10.5 to get the Disc brake setup into my 95. I understand ring and pinion should swap since I need 4.11 and I do have the long pinion from 93 and newer currently.

If you have done the swap, what did you do for a master cylinder?

I have rear disc brakes now, am thinking of going back to drum brakes, or swapping to 10.5 axle since I have other work to do anyway.

It just doesn't stop as hard as I think it should. I swapped to disc before hydroboost, even with hydroboost I think it should stop better.
 
Thee
fuck
what?
proofread man

LOL

Never heard of people swapping the 1999+ sterling 10.5 rear axle into an older 93-98 obs to get the dual piston caliper disc brake setup with e-brake?

but of course the 99 and up never came with a 4.10 ratio. So you have to swap Ring and pinion. The 10.25 Sterling is the same size ring and pinion from 1993 and up. They are called long pinion. 2nd design to fix something blah, blah blah.

Of course master cylinder is going to be different as the dual piston calipers will take a different amount of fluid to operate than a single piston caliper like I have now, or a wheel cylinder used on drum brakes. Doesn't do any good to swap axles if you don't get the correct master cylinder because the rear brakes won't operate properly.

Make sense?
 
LOL

Never heard of people swapping the 1999+ sterling 10.5 rear axle into an older 93-98 obs to get the dual piston caliper disc brake setup with e-brake?

but of course the 99 and up never came with a 4.10 ratio. So you have to swap Ring and pinion. The 10.25 Sterling is the same size ring and pinion from 1993 and up. They are called long pinion. 2nd design to fix something blah, blah blah.

Of course master cylinder is going to be different as the dual piston calipers will take a different amount of fluid to operate than a single piston caliper like I have now, or a wheel cylinder used on drum brakes. Doesn't do any good to swap axles if you don't get the correct master cylinder because the rear brakes won't operate properly.

Make sense?

No idea why you think they never came 4.10s. Lots of them were 4.10s. They never came with the 3.54s that the obs did.

As far as I read, it's basically a bolt in. Just have to mess with e brake cables, and wheel bolt pattern.
 
LOL

Never heard of people swapping the 1999+ sterling 10.5 rear axle into an older 93-98 obs to get the dual piston caliper disc brake setup with e-brake?

but of course the 99 and up never came with a 4.10 ratio. So you have to swap Ring and pinion. The 10.25 Sterling is the same size ring and pinion from 1993 and up. They are called long pinion. 2nd design to fix something blah, blah blah.

Of course master cylinder is going to be different as the dual piston calipers will take a different amount of fluid to operate than a single piston caliper like I have now, or a wheel cylinder used on drum brakes. Doesn't do any good to swap axles if you don't get the correct master cylinder because the rear brakes won't operate properly.

Make sense?

Was that so hard?
What you wrote made me guess at some of that!
I own an obs, helped swap in a idit obs dash and drivetrain into a brick nose, so "yes I heard of it" btw purty sure 4:10 is still an option for 10.5'

Oh and
Hydroboost! Ftw!:smokin:
 
but of course the 99 and up never came with a 4.10 ratio. So you have to swap Ring and pinion. The 10.25 Sterling is the same size ring and pinion from 1993 and up. They are called long pinion. 2nd design to fix something blah, blah blah.

4.10s were available from 99-2010.
 
Great, I guess I just haven't found any 4.10s. So was there a more common platform that they came in, like gas or diesel? 2 or 4x?

But the real question is what master cylinder?
Using the newer Super Duty master cylinder? Anyone know if the front calipers are the same cubic inch capacity as the 1999 and newer?
 
I have installed 2004 F350 axles/leafs into my 97 F250. Used PMF but wish I went with sky offroad designs. Way better parts.

Rear axle bolts right in, but the shocks are mounted differently. Ones forward facing and the other is rearward if that makes sense?

Use the Fsuper duty hydro boost unit with the vacuum master from the current truck. Will need to notch the holes a bit. As the Fsuperduty master will apply the rear brakes on braking before the fronts. Thinking maybe the super duty master might work too from a 99-04? Not sure. Have to re drill a hole on the brake pedal about 3/4 of an inch higher to allow the brake booster lever to be level or you with sometimes get a real hard pedal.

I do have the E brake set up in my truck (as I have a manual), but I have an issue with one of the cables stretching and not always holding the truck.

Just finishing lunch. Will add more/fix as I rushed the post.
 
Rear axle bolts right in, but the shocks are mounted differently. Ones forward facing and the other is rearward if that makes sense?

Use the Fsuper duty hydro boost unit with the vacuum master from the current truck. Will need to notch the holes a bit. As the Fsuperduty master will apply the rear brakes on braking before the fronts. Thinking maybe the super duty master might work too from a 99-04? Not sure. Have to re drill a hole on the brake pedal about 3/4 of an inch higher to allow the brake booster lever to be level or you with sometimes get a real hard pedal.

I saw the shock mounts, pretty simple to cut off and weld on, or weld on new ones in the OBS location.

I have moved the pin on the pedal, my pedal is still stiff, I think the power steering is not as good either. Swapped PS pumps and still disappointed. I think my Hydroboost needs to be ported. Maybe?

Currently I am running a master cylinder from a 99 expedition. It has dual piston front calipers and single piston rear calipers like my current setup. Spent a lot of time trying to make the brake system better, just don't seem to gain anything. Everything works like it should. Everything is matched to the job it is tasked to do. It will lock up the tires but I have to stand on it so hard I feel like I will rip the seat from the floor.

I have drilled and slotted front rotors, some fancy brake pads, but I am starting to believe they are not all their cracked up to be and maybe I should go back to OEM stuff.

Currently have RSK setup. I did it before X code was a thing. Did not notice a ride difference after install. All it really did is cause the truck to start using up front leaf springs.
Going to remove it. Lower the truck back down. Am thinking of going with 2" soft ride springs of just back to Factory. As I am getting older and in a few years I would not be able to crawl into the truck with the current 4" lift, nor be physically capable of restoring the OEM height.

Removing the lift would be a great time for a rear axle swap.

Master cylinders are cheap, I might try them both. My truck is heavier on the back than others so the applying the rear first is actually inviting.

Thanks.
 
X codes ride much stiffer use V codes and that will also lower 1-2"

Best option swap frt and rear axles to 99-04, rides better and steers better plus great brakes.
 
I swapped ‘04 axles into my ‘94 f250 basically a bolt in swap besides the center pin on the spring perches is 5/8” wider on both sides on the ‘04 front axle, as far as the rear shocks, the shock mounts are held on with ubolts and can be adjusted to the obs location or welded on. I’m running the factory obs master cylinder no issues, truck stops great and doesn’t lock up the rear brakes. I swapped my axles onto the factory TTB suspension in the beginning, but recently installed the pmf shackle reversal spring hanger and shackles, with stock excursion front springs and a 1” zero rate leaf in the front, ride ls like a Cadillac but I need to install a track bar, the front end feels loose but is drivable. Only complaint about the swap is that the turning radius is noticeably less than with the TTB, I may eventually install 05+ axles to regain my turning radius

photo49640.jpg


photo49641.jpg


photo49642.jpg


photo49643.jpg
 
Nice setup. I appreciate all the input.

I actually think I am going to cut the parts off a Dana 60 or 10.5 and weld them onto my 10.25. It eliminates some other problems, such as hub bolt patterns, track width doesn't change. I know bolting an axle in is probably easier but I like to do the custom work.

I still debate on what to do about suspension. I have 4" rsk now. Might just go back to factory height. Seems like I enjoyed driving my truck more. Who knows, that is up in the air yet.
 
Nice setup. I appreciate all the input.

I actually think I am going to cut the parts off a Dana 60 or 10.5 and weld them onto my 10.25. It eliminates some other problems, such as hub bolt patterns, track width doesn't change. I know bolting an axle in is probably easier but I like to do the custom work.

I still debate on what to do about suspension. I have 4" rsk now. Might just go back to factory height. Seems like I enjoyed driving my truck more. Who knows, that is up in the air yet.

The track width isnt as bad as you might think. I know on my 88 F250 the rear sterling is ~4" narrower then my front 60. The 99-04 sterling is 2" narrower.
 
Nice setup. I appreciate all the input.

I actually think I am going to cut the parts off a Dana 60 or 10.5 and weld them onto my 10.25. It eliminates some other problems, such as hub bolt patterns, track width doesn't change. I know bolting an axle in is probably easier but I like to do the custom work.

I still debate on what to do about suspension. I have 4" rsk now. Might just go back to factory height. Seems like I enjoyed driving my truck more. Who knows, that is up in the air yet.

Fwiw, early 2000s E350 and maybe E250 uses all the same brakes but is 8x6.5.

I honestly doubt you'll notice a huge difference in the rear disks. My buddy swapped a drum D80 for a disk one in his 96 dodge and said he noticed absolutely no difference. Drums work well when adjusted properly.

My next step is Fsuperduty hydroboost.
 
Fwiw, early 2000s E350 and maybe E250 uses all the same brakes but is 8x6.5.

Yes, I have learned a bunch there.
E250 were pretty much all gas engine, have a semi float rear end but use the same brake parts as the full float E350 rear ends.

They were an option from 1996 on, but looks like 96 & 97 have different calipers. they are pinned not bolted like the newer trucks.

not every van in that era will automatically have a disc brake rear end.

looks like at least 98 to 2003 will work. I had heard up to 2005.

For the most part my drum brakes worked really well for years, but first problem I had was trying to stop at the bottom of a hill and had no brakes. Brake fade got me. We were stuck in slow moving traffic, I could not gear down far enough to stay off the brake pedal. Being a rare occasion I left it. Seems like every since then I could never keep the drums working properly, I would get pulling left or right when I hit the brakes. But randomly, no mater how many times I put all new stuff on again. So I gave up went to discs. That was 2003 I believe. After working out some bugs it has been a flawless system. never had brake fad, no more pulling left or right when hitting the brakes. I still think it can be better.

Just bought a semi float rear end for $75. have all the parts I need, now need to start cutting apart.

Currently I have the single piston eldorado calipers, a 99 expedition master cylinder and hydro boost. System works really well. It was not easy getting this far. Just can't leave chevy parts on my ford though. lol

I think my biggest complaint is Power steering pump, hydro boost. Needs some porting or better pump or both. That is on the list as well.

I have taken an ir temp gun and checked rotor temps. Under normal braking the rear barely works. Under hard braking the rear is working harder than the front. That seems messed up to me. the 99 expedition master cylinder has been the closest match to the front and rear caliper piston volumes. Don't know where else to go. Make my own master cylinder?

In my mind they all 4 should lock up at the same time with much less pedal effort, and do more equal work.

This dual piston setup is a step to a completely equal 4 wheel braking system. I have a topper and a lot more weight in the back than standard pickups so what works for others doesn't work for me the same. Just want the best braking possible for my setup and for the pedal to feel like my 2014 super duty.
I will have more master cylinder options to match my piston volumes with the dual piston calipers.

Over the last 20 years with this truck it is hard to tell what gets messed up. Would be nice to go back to completely stock and start over because now you don't know if you are fighting poor engineering, faulty parts that I put on, or is everything working properly and this is all the better it gets?
Seems like fixing one problem creates another, going to a factory style setup using the E250 rear brakes I hope gets me back to some kind of baseline instead of always wondering where the failure is. I can start over with all new Ford quality parts and I will always be able to go to the book and know what master cylinder it should have, brake pads, everything that Ford engineered. then I can just tweak it to get the balance and pedal feel I want.

For most people drums brakes, disc conversion, hydroboost, any of it will be good enough, work great, they will be happy. I am like 10 levels above that point.
 
Just to add some actual tech here. I am in the middle of this install. I would not recommend cutting the flanges off another axle and welding them on yours, it is not a job for a novice or faint of heart.

Single piston caddy calipers have a piston bore of 54mm. With 1000 PSI of fluid pressure that creates 3549 pounds of force on the brake pads/rotor.

Compared to,
Dual piston calipers from 2000 E350 van with Dana with 60 rear axle. They have two 44.9mm diameter pistons. With 1000 pounds of fluid pressure each piston exerts 2454 pounds of force, 4908 total pounds of clamping force.

Super Duty rear calipers from 99 and up used 44.3 MM pistons. So essentially the same as the vans.

Front calipers on the OBS like 1995 F350 are a 56.1 mm piston. with 1000 pounds of fluid pressure each piston creates 3831 pounds of force. total 7622 pounds of clamping force.

So it looks like Dual piston rear calipers will be slightly better than single pistons, but still no where near the kind of work the front end is capable of doing.

Also master cylinders. I am running 1 1/4" bore, the E350 vans were 1 5/16" and Superduties are 1 3/8"

With 1 1/4" bore it will take less pedal effort to create 1000 PSI fluid pressure, but it will take longer pedal travel.

With the 1 3/8" being the opposite. Less pedal travel but more leg effort to create 1000 psi.

I am still running through the factory rear ABS valve. I have no proportioning valve, The fitting on the master cylinder going to the rear brakes has been gutted years ago.

Probably won't change master cylinders until I drive it and take some temperature readings. I am in the process upgrading my PS pump to a 2005 6.0 diesel steering pump. Waiting to see how that will affect my hydroboost/pedal feel first.
 
I'm about to start this swap right now. Just need to swap the shock mount around and get some u-bolts. I'm doing a shackle flip in the rear so I can eliminate the block at the same time.
 
I'm about to start this swap right now. Just need to swap the shock mount around and get some u-bolts. I'm doing a shackle flip in the rear so I can eliminate the block at the same time.
Are you doing just the rear axle?

How are you dealing with the hub/bolt pattern issue?
 
Top Back Refresh