1989 IH S1900/dt466 Rear Brake Change

I just got my DOT inspection done, and I have to change one of the rear brakes on my International S1900 dt466 because it's just below the 20% mark. Instead of doing only one brake, I am planning on changing both sets of rear brakes next weekend.

Does anyone know the bearing torque procedure that I need to use when I reassemble the hubs? Are there any special procedures or gotchas that I should know about? This truck has air brakes and Detroit wheels.

farious said:

I just got my DOT inspection done, and I have to change one of the rear brakes on my International S1900 dt466 because it's just below the 20% mark. Instead of doing only one brake, I am planning on changing both sets of rear brakes next weekend.

Does anyone know the bearing torque procedure that I need to use when I reassemble the hubs? Are there any special procedures or gotchas that I should know about? This truck has air brakes and Detroit wheels.

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Detroit wheels??? Haven't heard that before. I have to ask what we don't know; have you ever serviced drive axle hubs or air brakes before?

Detroit Wheels

ATCOEQUIP said:

Detroit wheels??? Haven't heard that before. I have to ask what we don't know; have you ever serviced drive axle hubs or air brakes before?

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That is what the gentleman at the parts department called them - I have the hubs that require a complete hub disassembly to get at the brakes, instead of the type where you can just take off the lug nuts and remove the wheels and brake drums that are common on lighter duty trucks and cars.

This will be my first attempt at air brakes, but I have worked on this style of axles and hubs before.

I am most concerned with the torquing procedure for the wheel bearings. I asked someone who works on these trucks the correct procedure, but "tighten it until it feels right" didn't give me a great deal of confidence in the advice I received.

I think farious is talking about a "dayton" style spoke wheel on the IH truck.On any wheel hub big or small I torque them down while spinning the wheel by hand untill I feel some resistance on the hub ,then back the nut off about 1/3 of a turn on the axil threads.It's better to have a bearing a little loose as to tight.

Torquing

25c said:

I think farious is talking about a "dayton" style spoke wheel on the IH truck.On any wheel hub big or small I torque them down while spinning the wheel by hand untill I feel some resistance on the hub ,then back the nut off about 1/3 of a turn on the axil threads.It's better to have a bearing a little loose as to tight.

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Sorry about that - I thought he said "detroit".

The mechanic I talked to said that on IH trucks there was a seal inside of the hub that made it always feel like there was too much resistance, and you really couldn't judge by the resistance you felt on the hub. Is that true? Would it be possible to measure end play in the hub with a dial indicator to get the correct torque?

On smaller trucks, usually you torque the bearing tight to get it into position, back it out, torque it to spec, then back off 1/3 to 1/2 a turn. Is it the same on larger trucks?

farious said:

Sorry about that - I thought he said "detroit".

The mechanic I talked to said that on IH trucks there was a seal inside of the hub that made it always feel like there was too much resistance, and you really couldn't judge by the resistance you felt on the hub. Is that true? Would it be possible to measure end play in the hub with a dial indicator to get the correct torque?

On smaller trucks, usually you torque the bearing tight to get it into position, back it out, torque it to spec, then back off 1/3 to 1/2 a turn. Is it the same on larger trucks?

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LoL, I was thinking Dayton rims as well 25c.

The hub seal he is referring to is probably what's called a "two piece seal". They do create some "free wheeling" resistance. I'm sure there is a proper procedure for it, but I do the same as 25c, just feel my way in there. I guess from doing so many hubs/bearings over the years, we're just used to feeling it in.

farious said:

This will be my first attempt at air brakes.

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Well, one of the first things you have to do is back off the brake adjustment at the slack adjusters to remove the brake drums. Have you done this before? Does it have manual slack adjuster or self adjusting?

farious,It's the same on all vehicals that use a tapered bearing big or small.Torque it down tight to seat everything ,then back the nut off 1/3 of a turn.

Slack Adjusters

ATCOEQUIP said:

Well, one of the first things you have to do is back off the brake adjustment at the slack adjusters to remove the brake drums. Have you done this before? Does it have manual slack adjuster or self adjusting?

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I just checked the truck. They're manual adjusters. I've adjusted this style on another truck before, but I'm not sure if I used the correct procedure - I moved the pivot in the slot until the in and out play was under the spec for that diameter air pod. I assume that I'll move the pivot point to remove the most pressure from the drum as I can.

farious said:

I just checked the truck. They're manual adjusters. I've adjusted this style on another truck before, but I'm not sure if I used the correct procedure - I moved the pivot in the slot until the in and out play was under the spec for that diameter air pod. I assume that I'll move the pivot point to remove the most pressure from the drum as I can.

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I'm not certain what your describing. I've never tried to explain brake service procedure on a forum, not so easy to do. I assume your have typical S-cam type brakes similar to the pic below.



If so, you probably are working with dual chamber spring brake pots on the rear axle which applies the parking brake. I trust you have the axle supported by sufficient stands to remove the wheels. You need to first release the parking brake either manually or by releasing parking brake with air valve in cab. Then, you want to rotate the brake cam shaft by turning the adjusting screw on the slack adjuster. You want the cam shaft to rotate in the direction opposite of the direction that applies the brakes. Rotate the cam shaft until the brake shoe rollers bottom out in that "hook" of the S cam. Then, apply the parking brake with cab air valve, now you can finish releasing the brakes with the adjusting screw until it bottoms out on S cam. You're now ready to remove brake drum.

I just picked up a nice vise in some horse trading and I want to make a stand for it as my work benches are all occupied with other equipment that I don't want to move.
I am advertising on Craigslist and FreeCycle for a "Budd" wheel,20/22/24" and maybe an axle too if they have one so I can take it apart if I have to but I have not gotten any hits in about a week.I will probably have to start knocking on doors to find what I am looking for.Ron G

RonG said:

I just picked up a nice vise in some horse trading and I want to make a stand for it as my work benches are all occupied with other equipment that I don't want to move.
I am advertising on Craigslist and FreeCycle for a "Budd" wheel,20/22/24" and maybe an axle too if they have one so I can take it apart if I have to but I have not gotten any hits in about a week.I will probably have to start knocking on doors to find what I am looking for.Ron G

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I hope you get that sorted out Ron. Two tools I couldn't do without is my vise and my hammers.

If you want some numbers to go by, SKF bearing states tighten while turning to 200 ft lbs, back off a full turn, tighten while turning to 50 ft lbs, then back off 1/8th or as needed to get the lock ring on a pin.

OH! I just remembered a great trick for that style of hub.. Ok so you leave the duals in place and don't tear the tires off the hub/drum assembly. Just whack the axle loose and pull it out. Then get 3 important items. 1.A big bottle jack 2. A flat clean piece of aluminum.(like a street sign, but not a street sign, that's illegal) 3. A cup full of oil.

Jack up the wheel assembly you are pulling off, pour the oil on the center of the sheet metal, then slide then slide it under the tires so the oil is directly under the rubber.

Now lower the jack until the rubber just hits the oil. Now pull out the bearing retainers and the outer bearing. Then slide your complete tire, hub, drum assembly straight off the spindle. If it doesn't slide easy move the jack up or down a little. But once it is right that huge heavy assembly will slide in the oil over the smooth metal like butter drippin' off a hot biscuit. And if you have a good jack that doesn't bleed down it will go back on just as easy. I used this technique over a wheel dolly.

Great Trick

Muffler Bearing said:

OH! I just remembered a great trick for that style of hub.. Ok so you leave the duals in place and don't tear the tires off the hub/drum assembly. Just whack the axle loose and pull it out. Then get 3 important items. 1.A big bottle jack 2. A flat clean piece of aluminum.(like a street sign, but not a street sign, that's illegal) 3. A cup full of oil.

Jack up the wheel assembly you are pulling off, pour the oil on the center of the sheet metal, then slide then slide it under the tires so the oil is directly under the rubber.

Now lower the jack until the rubber just hits the oil. Now pull out the bearing retainers and the outer bearing. Then slide your complete tire, hub, drum assembly straight off the spindle. If it doesn't slide easy move the jack up or down a little. But once it is right that huge heavy assembly will slide in the oil over the smooth metal like butter drippin' off a hot biscuit. And if you have a good jack that doesn't bleed down it will go back on just as easy. I used this technique over a wheel dolly.

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You aren't kidding - that is a great trick. I think disassembling and reassembling that wheel assembly would take almost as long as the whole rest of the job! I am definitely going to try this.

Bearing Procedure

Muffler Bearing said:

If you want some numbers to go by, SKF bearing states tighten while turning to 200 ft lbs, back off a full turn, tighten while turning to 50 ft lbs, then back off 1/8th or as needed to get the lock ring on a pin.

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That sounds very similar to the procedure used on light trucks - the initial tightening is to ensure that the bearing is set, and then the second is the actual tightness. I will try this, as well as check the friction against what it feels like when I take the old assembly off. You're about the third person who has told me the 50 ft-lb number.

farious said:

That sounds very similar to the procedure used on light trucks - the initial tightening is to ensure that the bearing is set, and then the second is the actual tightness. I will try this, as well as check the friction against what it feels like when I take the old assembly off. You're about the third person who has told me the 50 ft-lb number.

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I will quote your quote of his quote........:cool2

Thats the way i was taught and it hasnt led me a stray yet, the only difference is i just back it off until its "finger tight" instead of a ful turn but..... tomato potatoe if you ask me

Some Questions

I started to work on this today, and I have some questions:

* Is there any easy way to get the springs back on other than just forcing them in? I spent almost an hour to get the front spring in, and still wasn't able to get it.
* The rear brake pivot had a thin metal ring around it. The old ones had this as well. I took one of the old ones out with a chisel, but it was very difficult to do. Can I keep the old ones in place, or should I replace them?
* I took the tires off because I decided to repaint the rims while I had everything apart, but now I think I might have made a mistake because the hub and drum assembly is so heavy. Should I put it back on with a cherry picker, or would it be better to reassemble everything off the truck and use a dolly to slide it back on?
* The lug nuts were so tight I had to jump on a 4' breaker bar on the end of a 3/4" ratchet. No other truck (even my F800) has ever had lug nuts this tight. Is this normal for Internationals?
* The outer axle seals seemed to be missing, and RTV sealant was used. Is this acceptable practice, or should I order outer axle seals?
* Is there a difference between the upper and lower brake shoe? They looked identical to me, but I want to be sure.

farious said:

I started to work on this today, and I have some questions:

* Is there any easy way to get the springs back on other than just forcing them in? I spent almost an hour to get the front spring in, and still wasn't able to get it.

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I assume you have S-cam type brakes. Are they like the pic below. If so, here's the easiest way I've found of removing and re-install of the shoes
Make sure the S cam rollers are at the bottom of the cam nautilus. Place a prybar against the inside of the shoe, in the area of the front spring, lodge the tip of the prybar against something on the backing plate that will allow you to lift the shoe like brakes being applied. When you've raised the shoe enough, drop out the S cam roller on the front of the shoe. Do the one that's open to the outside first, that would be the top one in the pic. Do the same procedure for the other shoe. With these rollers removed the front spring is easily removed. With the front spring removed, pivot the lower shoe down and backwards. It will pivot on a radius slightly stretching rear springs, but will break over a spring stretch center point and the begin to loosen springs until they're so loose the will practically fall out. Re-assemble brakes in reverse order. The last things you install is prying the S cam rollers back in.

Ok, I'll skip the first question for now, onto the second: I usually leave the metal sleeve in place for several brake jobs, unless it really starts to wear. But since you have them out go ahead and change them, new ones come with the brake hardware.
I bet with another strong back helping you could get that hub drum assembly back on, but be careful you don't hurt your new seal. It really is easier to line every thing up when you have the tires mounted to the rims. Either way you go just watch the seal.
Tight lugnuts are normal
Forget axle gaskets just use RTV
Both shoes are identical.