71' F250 Brake Job

[martinarcher]

Hey guys!

What a great site. I finally joined up. Your site has been a great resource when working on my F250.

I'm starting on a brake job. Last year I did the front brakes (drums). I replaced all the springs, adjusters, cables, and had the drums turned and put new Bendix pads on.

I tow our Malibu ski boat with this truck and the brakes have been nothing to brag about. I get little to no braking until the petal almost reaches the floor. I decided since the brake fluid gets a little low now and again and is dirty looking I'll do a full overhaul. Since the front brakes are new, I figured I'd dig into the rears since I have't had the drums off since I bought the truck.

I started on the back axle tonight and realized I need to pull the axle out to get the drums off - that is a bummer! I then realized I have to pull the bearing locknut and the whole hub - dang!

I also bought a reman Bendix master cylinder I will be installing. The master cylinder on the truck now has a larger rear reservoir and a smaller front. I thought that was a little strange since it has four wheel drums. The reman master cylinder I got from Advance has two reservoirs that are the same size. I did some digging around on the site and it looks like it is just the older style master cylinder. Am I right on this??? After I get the master cylinder on I can bleed the brakes and hopefully get braking much sooner than when the petal reaches the floor!

So....sorry for the large post, but I have a few questions...

1. Is the master cylinder OK for my truck or should I take it back for one that has a large rear reservoir?
2. Is the rear reservoir for the front brakes? I assume it is since it is larger?
3. Do they make a wrench for the bearing locknut? I have one for the front, but it doesn't fit. I hate to bang it out with a screwdriver and a hammer.
4. How tight does bearing adjuster nut go when I put it all back together?
5. I pulled the right rear axle out and no fluid rolled out? I assume this is bad news. The rear end doesn't make any noise. I plan to pull the diff cover off and inspect the diff. What oil should I use to fill it back up?

Sorry for all the questions, but this is my first time digging into a pre-80's rear end. I'm familiar with the 80's Bronco brakes, but this is sure a different ballgame!

Thanks a million in advance!

Now for pics of the truck!

[fireguywtc]

First off and nice pickup, love the 4x4's!

as for the master cylinder I am a little fuzzy on your question. Did you buy a new one and it looks different then the old one. If it is different I would take it back, If it is the same put the front brake lines to the larger resivor.

For the bearing locknut again Im not too sure about the wrench question. Are you in need of a larger one or is it special shape, (pics help) When you do tighten back on after you repack the bearings, I am not aware of any exact spec. I tightent the nut until it is tight and puts a little pressure when turning the hub, then I back it out just a little bit so the hub turns freely but there is no slack.

With the rearend oil I don't have a specific recommendation because it can vary. If you have a locking diff remember friction modifer and I would also recommend using sythetic oil and changing all the drive train fluids to sythetic at the same time. I think you will like the difference!

[fordman]

the resiovor size for 4 drums is suppose to be the same size on both. probably the master has been replaced beofre witha disc drum master. and that could be the difference and or the problem with hardly no brakes.

[martinarcher]

First off and nice pickup, love the 4x4's!

as for the master cylinder I am a little fuzzy on your question. Did you buy a new one and it looks different then the old one. If it is different I would take it back, If it is the same put the front brake lines to the larger resivor.

For the bearing locknut again Im not too sure about the wrench question. Are you in need of a larger one or is it special shape, (pics help) When you do tighten back on after you repack the bearings, I am not aware of any exact spec. I tightent the nut until it is tight and puts a little pressure when turning the hub, then I back it out just a little bit so the hub turns freely but there is no slack.

With the rearend oil I don't have a specific recommendation because it can vary. If you have a locking diff remember friction modifer and I would also recommend using sythetic oil and changing all the drive train fluids to sythetic at the same time. I think you will like the difference!

That's right, the one on the truck now has a larger rear reservoir(which I assume runs the front brakes) and a smaller front one. The Bendix master cylinder I got at that parts store has two reservoirs of the same size.

I'll see if I can get some pics of it tomorrow (getting in bed now). I got the right side all apart tonight and did it with a screwdriver and a hammer (looks like it had been done that way before). I figure it would be impossible to get a specified torque on the bearing adjuster nut without a socket for the nut.

After getting the whole hub/drum assembly off, can you get that bad boy turned? It is huge, and still has the entire inner bearing in it and the race for the outer bearing. I would be worried of getting shavings in the bearings, unless you change them after turning it.

My father in law gave me a couple gallons of synthetic gear oil. I need to check on the weight. Can I figure out if it is a limited slip or locker by looking at the axle?

Thanks!

[martinarcher]

the resiovor size for 4 drums is suppose to be the same size on both. probably the master has been replaced beofre witha disc drum master. and that could be the difference and or the problem with hardly no brakes.

That's what I was wondering. I'll post up some pics of both master cylinders tomorrow and you guys can let me know what you think. I'm thinking your right. I would think all four wheel cylinders on a four drum truck would require roughly the same amount of fluid.

[fordman]

you can look at the tag number onthe rearend to find out if its a locker. unless the tag is gone. one way to find out is to turn one wheel while having both wheels off the ground. if they both turn the same way when you turn one tire only it is a locker. if one wheel turn the opposite way when you turn one wheel then its not a locker. yes i just checked that other thread and i was correct you do need the same size master resivors for the all drum system.

[fireguywtc]

If you are taking off the diff cover, you will be able to see if it is a locker. You will be able to see the clutches in the axel.

[SteveC]

i didnt have to pull the axles on my f-250 to service the drums on my 67 there were three screws that held the drum on to the axle and i was able to pull the drum off after getting those out, maybe 4x4's are different

[sideoilerfe]

i didnt have to pull the axles on my f-250 to service the drums on my 67 there were three screws that held the drum on to the axle and i was able to pull the drum off after getting those out, maybe 4x4's are different

They changed them in 69 or so. My 65 and my 68 are like yours but my 70 and 72 you have to pull the axle out.

[SteveC]

ah thats good to know... i learned something today...... and in some ways glad i didnt keep my 72 a f250...and made it a f100 instead

[sideoilerfe]

It's not a big deal to pull those axles in the F250's. I like the older design better but the newer ones are not hard to work on.

[FLATBEDFORD]

4 wheel drums use a maser cylinder with two equal sized chambers. The rear chamber is for the front brakes.
You can buy the socket for the lock nut at an auto parts store. I think it's 2 9/16"

[martinarcher]

Good deal - thanks for the replies guys. You have been a huge help.

I guess I'll throw the master cylinder i got form the parts store on - that could be the reason for my horrible braking.

Yep - pulling the axle wasn't too bad at all.

I'll look for that bearing nut socket tonight at the parts store on the way home from work. The nuts are huge.

I guess my rear end isn't a locker. I remember when I was trying to get the axle adapter off (breaking the eight bolts loose that hold the axle to the hub), the other wheel was spinning the opposite way.

One more question.... To get this drum turned, do I have to knock the wheel studs out to seperate the hub and drum? Thats what it looks like.

Thanks again guys.

[FLATBEDFORD]

My F350 has a Dana 70, but I think the 60 is the same. If you knock the studs out, the drum and hub will separate. You should replace the inner seals while you have it apart. That way you can also get the inner bearing out so you can inspect and clean it, and metal shavings won't be an issue if you have the drum cut. You can carefully tap the new ones in with a hammer. Just go slowly and work all the way around so it doesn't go in crooked and bind up on you. VERY important; make sure the inner bearing is in place before you install the seal.
Fresh oil in the rear end would also be nice. I bought the gaskets for the diff cover and the axle end plates too. I think some here think it is better to use RTV sealant than the gaskets. I can't say what's better, but I have no leaks yet.

By the way. That is a nice looking truck.

[martinarcher]

Thanks Steve - we like it a lot and it has served us well.

Good deal. I planned on buying new axle and diff cover seals and filling the rear end with synthetic gear oil. Does 90WT sound right?

I will tap the studs out tonight and get the drum cut. I can have the guys at work press the studs back in with the hydraulic press.

Good call on getting the bearing in before the seal. It is easy to get ahead of yourself putting things back together - been there done that. Nothing like an extra trip to the parts store for a whoops.

When I did the front bearings last year, I pulled everything apart cleaned the hub, nuts and lockwasher, put new Timken bearings in and greased everything with Mobil 1's synthetic bearing grease. I was happy with how everything turned out. I'll go the same route with the rear end.

Thanks for the continued help. I really appreciate it.