What to expect when pulling Dana 70 drums...

[The Warden]

If it's not one thing, it's another... *sigh*

After replacing my battery cables, replacing the pyro, and getting the glow plug system together (still working on the finishing touches, but still), I took my truck for a drive this evening. This is the first time I've driven the truck since late January, but my truck's sat for considerably longer than this in the past without any problems.

Well, after driving around for maybe 5 miles, I got home...and noticed a weird smell. I thought it was electrical at first, so I sniffed all around the cab and under the hood and didn't smell anything unusual. I then went to the back of the truck and realized that the smell was coming from the rear brakes. I then realized that it had seemed like the truck had a bit less power than usual, even though I know that I had released the parking brake (I even double-checked the brake lever to make sure it was released)...and came to the conclusion that the parking brake didn't fully release and that the brakes were dragging. On closer inspection, I saw smoke coming from the right rear drum...the left rear drum seemed okay, though. I then rolled the truck forward, and it actually rolled freely for about one wheel revolution and then bogged down.

I talked with my dad about this, and he said that it's consistent with a broken spring inside the right rear drum...does that make sense? If not, what should I be looking at in the E-brake system? Again, as best as I can tell, only the right side failed to release...although I haven't jacked the truck up to check this, based on the lack of smoke, heat, and smell on the left side, I think the left side's okay (although I certainly need to do hardware for both).

In any event, it looks like I have a brake job ahead of me...and this is the first time I've ever done a drum brake set, so I'm more than a little bit nervous. What should I expect, particularly with things overheating due to the brake shoe sticking? I haven't had a chance to look through my manual yet to see what all it entails, but I know that I have to pull the axleshaft (therefore needing to drain the differential) on the Dana 70 before even thinking about getting the drum off.

Any thoughts would be appreciated...and I know that D_C is going to be at me, but hopefully he won't be rude about it.

Thank you!

 

[Roland_Jenkins]

You don't "have" to drain the diff unless you are due for a oil change.
It goes something like this.

Put the rear axle up on jack stands, block the front wheels.
Back the brakes off. Otherwise, If the drums are grooved you might not be able to pull the drum.

Pull the aforementioned axles. Don't lose the axlel seals. Have a couple of cans around to catch what little oil comes out.

Lift the locking tab on the star washer to free the spindle nut.
If you have a spindle wrench, loosen and remove the nut. Otherwise use a large screw driver or punch. Lefty loosey, righty tighty.
Remove the star washer. Remove second spindle nut. You probably have another large flat tabbed washer in there. Pull the hub, watch your toes.

 

[MIDNIGHT RIDER]

The first place I would look is the parking-brake cable on the offending side, especially since the truck has been idle for a few days.

The inner cable will swell up and bind in the sheath.

Next thing would be one of the retainers jumped off; this is quite common, especially if the brakes get out of adjustment.

Brake return spring rusted in two is possible.

Another hard to diagnose situation is a bent shoe; the bent edge will grab the drum and spread the shoes.

It only needs be bent a very little.

 

[MIDNIGHT RIDER]

Lift the locking tab on the star washer to free the spindle nut.
If you have a spindle wrench, loosen and remove the nut. Otherwise use a large screw driver or punch. Lefty loosey, righty tighty.
Remove the star washer. Remove second spindle nut. You probably have another large flat tabbed washer in there. Pull the hub, watch your toes.

He most likely won't have the good two-spindle-nut-and-tabbed-lock-washer system.

What he will most likely have is the single nut with nylon insert and a little keeper driven into the nylon of the nut.

If this is the case, pick up a set of the good double spindle nuts and keeper/washers; as, the single nut is very soft and will let the bearing eat into the back side of it, thereby loosening the bearing adjustment.

 

[94f450sd]

shouldnt have to pull the axles.thedrums should come right off like the 10.25 rear axle.atleast thats how my dana 70HD is.it uses the same drum,shoes,hardware,wheel cylinder and backing plate as the 10.25 axle.from sitting so long you most likely just have rust built up in the drums.and when rolling the truck the drag you feel isprobably the shoes catching on the rust.my 95 does this if it sits for more than a week.

 

[NapaBavarian]

f450sd- perhaps they changed that later(as well they should have!), my '85 and my '77 both required me to pull the axles before the drums

 

[94f450sd]

maybe they did.havent touched the older trucks in a few years.now i get mostly early 90s and up trucks in the shop

 

[The Warden]

FWIW, the factory manual specifically states that the axleshafts need to come out before the drums can be pulled. I think the brake hardware is different as well, but I've never pulled a 10.25" either...as I said, while I've done front and rear discs, I've never done a drum brake assembly at all, and while there's a first time for everything I'm still very nervous about it...don't want to foul up. So, the most basic answers would not be a bad thing...

IIRC a spring kit can be purchased, and I should replace all the springs while I replace the shoes...is there anything else I should be replacing while I'm in there? Especially since one side overheated. Do I need any special tools? IIRC, the 10.25" has some special ratcheting nut that has to be removed before the drum comes off, but again IIRC the Dana 70 doesn't have that.

Rich, I see what you're talking about with rust buildup, but as I said, this has never happened before...and the truck has sat for much longer periods than this. When my uncle still had it, the truck could sit for almost a full year between drives, and the truck sat for 4 months in '04 when I did the head gaskets, turbo, etc. and had no problem whatsoever.

Rider, the manual mentions a locknut, lockwasher, and adjusting nut that need to be pulled before the drum comes off...is this what you're referring to? If that's not the "good" setup, can the other setup still be purchased anywhere? I have a feeling that it's a Ford-only part.

Thank you all again... *sigh*

 

[Meta6981]

Bad can of worms Tim. I would like to help you out but my plate is full for today unless it is later and even then its a maybe. We'll see I'll give you a call later. I have never heard of drum brakes that you had to pull the axle to access them.

 

[The Warden]

Bad can of worms tim. I would like to help you out but my plate is full for today unlass it is later. We'll see i'll give you a call later. I have never heard of drum brakes that you had to pull the axle to access them.

Except for Rich's truck (and other later dualies, I imagine), I believe that ALL Dana full-floating axles are set up like this. I know my old van was.

I won't be getting to the brakes immediately...I have to do the injection timing first (so I can get the equipment back to towcat in a timely manner), so I might not even be able to get to the brakes today. OTOH, I just looked at a weather report... It's supposed to rain off and on all next week. I hate to say this, but I might have to take the truck into a shop for the brakes...I don't have a covered area to work on the truck in (can't steal the carport area), and I NEED the truck next weekend (I've already put this trip off twice, and can't put it off a third time)...

 

[Agnem]

Rich, I'd need to see proof that a Dana 70 with removable drums exists, before I'll believe your claim. Not trying to disagree with you, but I've never seen or heard of one before. The Ford 10.25 looks so much like a Dana 70, that it would be easy to be mistaken. I sure WISH one exists, especially on the Moose Truck, as I never venture into the brakes except a couple times a decade because it is such a PITA. Warden, I expect you'll have exactly what was described. Just jack up the side your doing. That will make most of the oil run back down the axle tube. What is captured in the bearing area will still run out when you pull it, but you can suffer the loss without any serious consequences. The little keeper and plastic nut deal is re-usable, but you have to end up with the nut stopping in a spot where the keeper can nail ****** nylon. If not, Ford says use a new nut. Be sure to check the concetricity of your drum, and get a new rear seal and axle to hub gasket before you start.

 

[MIDNIGHT RIDER]

The lock-nut, lock-washer, adjusting-nut set-up is the good one.

Your truck is probably new enough to have the sorry single-nut and keeper deal.

My 85 F-350 has the single-nut; but, as soon as I get to a junk-yard where there are some old Dana 60's or 70's laying around, that junk will be history.

I have the double-nut/lock washer deal on both axles of one trailer and on the Dana 60 under my old Chevy; and, if I haven't found a set by the next time I go into the hubs, I will trade out with one of these less critical axles.

The guys at the local dealership will not re-use the single-nuts; but, they just replace them with more sorry single-nuts to the tune of about $30 each.

 

[towcat]

I hate to say this, but I might have to take the truck into a shop for the brakes...I don't have a covered area to work on the truck in (can't steal the carport area), and I NEED the truck next weekend (I've already put this trip off twice, and can't put it off a third time)...

tim-
do be on the lookout for the little metal "wedge" on the keyway when you tear things down. If you do want to have a shop take care of it, I can arrainge the labor to be taken care of over at Mr. Kawano's. He is prolly the most reasonable and competent.

 

[The Warden]

If you do want to have a shop take care of it, I can arrainge the labor to be taken care of over at Mr. Kawano's. He is prolly the most reasonable and competent.

Oh! I didn't know he did axle work as well...I think I'll take you up on that, unless the weather makes a significant turn for the better in the next 24 hours or so. Not having a garage is no fun at all!

 

[Agnem]

What is so bad about the single nut deal? I've had it for 23 years with no problems.