Last week I observed a weird issue with the brakes on my 450....
When backing up...the brakes made a sound as if the parking brake was still applied. It sounded like a metal grinding sound. Then while braking...the truck seemed to stop normally enough but the brakes would grab much harder during the last 10-15 feet before coming to a dead stop.

So, I decided it was time to inspect the brakes....something that was on my 'list' of things to do but somehow never managed to get around to it ever since I purchased the truck about 18 months ago. I checked the front brakes but the rears were a mystery to me. Well, now it's not a mystery any longer because my laziness cost me over $300 in parts and many hours of labor.

There are lots of great write ups on changing brakes so I won't rehash any of that here but I figured I'd post up the procedure I used since it appears the F-450 is a bit different from the pickup trucks. The first thing you will notice is the brake rotor, pads, hub and axles are much larger...which makes sense. What I didn't expect was the slide pins to be so different. The style of the F-450/550 trucks are such that the pins can be removed and lubed without having to pull the wheels. I guess this is a pretty cool feature....if I would have utilized it. You will see what happened to the rotors in the first pic.

As far as I can tell, even thought the F-350 DRW and F-450 7.3 trucks share the Dana 80 differential....the axle shafts and running gear are completely different. The special spindle nut tool that works so well on the F-350 trucks won't do you any good on the 450s (unfortunately). The tool you need is a thin wall 8 sided 3 1/4" socket...I purchased mine from NAPA for $34.

It's best to do one side at a time....this way you don't loose too much gear oil when you pull the axle out. The F-450/550 trucks come with a hydraulic bottle jack...use it. It fits perfectly in the cast iron bracket for the U-bolts. Jack up one side at a time so the wheels are about 1 1/2" - 2" off the ground. Any more than that and you will struggle to get the wheels off and back on (they are super heavy).

1. Remove the brake caliper and hang it to the side.
2. Remove the caliper anchor plate. You are going to need a really big breaker bar or impact gun because the bolts are very tight!
3. Remove the 8 bolts holding the axle flange to the hub
4. remove the axle
5. remove the large spindle nut and outer bearing pack
6. protect the spindle threads
7. remove the hub/rotor assembly (very heavy)
8. place the hub assembly in a wheel and then remove the 10 bolts holding the rotor to the hub
9. remove the rear hub seal (will need a new seal)
10. remove the inner bearing pack.
11. Inspect the bearings and races, lightly grease and re-use if in good condition (the grease provides lubrication until the gear oil can take over)
12. Reinstall inner bearing pack in hub
13. Install new rear hub seal
14. Attach new rotor to hub. Torque bolts to 80 ft/lbs
15. Reinstall hub assembly onto spindle (adjust parking brake assembly if needed)
16. fill hub with some gear lube to replace what was lost
17. Install outer bearing pack
18. Install large spindle nut. Torque to 78 ft/lbs, then loosen nut 90 degrees and re-torque to 18 fts. Should be zero play in bearings but hub should spin freely, less than 25 ft/lbs to rotate hub.
19. Check o-ring on axle flange, replace if damaged.
20. Reinstall axle shaft and bolts, lightly tightened
21. Install caliper anchor plate, torque bolts to 295 ft/lbs
22. Lube caliper slide pins and verify free movement.
23. Install caliper and torque bolts to 41 ft/lbs
24. Bleed calipers if necessary
25. Install wheels, torque lug nuts to 165 ft/lbs
26. Lower vehicle to ground and torque axle flange nuts to 98 ft/lbs

Repeat for other side and final check diff fluid level when finished.

 

Your truck is about the same as my 97 F-Superduty.

 

I forgot how much more truck the old 450/550s were compared to 350s than the new ones. Makes the new 450/550s look like over rated 350s. Literally.

 

Yeah, the 2011 and newer F-450 pickups are really just the F-350 with a 4.30 gear. However, the new chassis cab F-450/550 still have the larger axles, brakes etc.

 

I was hoping it would be a simple job like my SRW trucks but that turned out to be just a bit too much for wishful thinking. My back was sore afterwards....I guess my age is catching up to me...

 

I hear ya. Working on over the road trucks has taken its toll on my back, as well. Those brakes and rotors are a little smaller than what I'm used to.

 

I almost broke out the transmission jack but I manned up and muscled it on there. Any heavier and I would have need some sort of help though. I can't imagine working on anything bigger.

I actually got a quote from a shop that does work on our fleet trucks and it turned out to be around $1200. That was when I decided how I was going to spend my weekend at home. My back was sore but at least my wallet was happy.

 

My 97 actually has a little smaller spindle than the later 450's. It has one of those racheting nuts like the 250's and 350's, except it's a little bigger. 2.125" threads instead of the 2.000" like the smaller trucks. The inner bearing journal on your truck is 2.8125" where mine is 2.625". Your outer bearing is 2.500" where mine is 2.1654". You've got a 3.500" wheel seal and I have a 3.250". Your axle is a little heavier. Did you fill the hub cavity with oil when putting it back together?

 

First - Fantastic write-up!

Second - I just skimmed because of a time thing I have now, but I saw nothing on the park brake. This was a serious problem on Stinky and he got the whole works.

 

The park brake assembly looked OK from the picture. As long as everything works, nothing froze up, I would think it should be fine. My 97 has the emergency brakes on the back of the transmission. That is a very bad design in my opinion.

 

No I didn't....wasn't aware that I needed to do that.
I did check the diff fluid when I got it back together and added a tiny bit....perhaps I should check it again now that I have put about 100 miles on the unit?

 

A lot of times, there's enough oil on the bearings to keep them lubed till the oil makes it out there while driving, especially if it's empty. Some guys pack the bearings with grease. I do not recommend that. Reason being, if you put a lot of grease on the outer bearing, it prevents oil from flowing through it to reach the inner bearing. Some guys like to lean the trucks for the oil to flow out to the hubs. Sometimes that works, sometimes not. I like to slide the hub on the spindle, then squirt some gear oil in the hub before putting the outer bearing on the spindle. If you're working on a chevy, you need to put the oil in the hub before putting it on the axle. They have a silly design where you install the outer bearing through the inside of the hub. A real PITA!

 

Nice tip. Thanks!
I coated the bearings with grease since that is what the service manual said to do. Squirting some gear oil into the hub prior to closing it up makes a lot of sense. I wish I would have thought of that at the time. I didn't go crazy with the grease on the bearings so hopefully I am going to be OK.....I think I'll check the level in the diff again just for some added piece of mind.

 

Putting grease on the bearings was a very common practice, and is certainly better than dry. But today it is recommended that you use oil, and fill the hub.

Spindles are my business. Usually if there is a problem with re-assembly, it rears its ugly head within 50 miles.

 

Nice looking rotors. I bet they work nice.
My parking shoes and parts were still in descent shape. Our climate here is normally pretty kind to chassis components so stuff like parking brakes and backing plates last the life of the vehicle in most cases. I probably should have taken a little time to adjust them though. They don't hold as strong now as they did before I changed the rotors. Maybe there is a way that I can adjust them from under the truck....I'll check that out tonight after work.