680H Air Brake Chamber question...

OVERTORQUED · May 25, 2019

Hi all- been a little while. Does anyone know of any place open in and around East Bay, CA that I can find air brake chambers? NAPA doesn’t stock anything around here and my searches on web aren’t coming up with anything. Big rigs don’t stop running, so they have to get them somewhere right? Any info greatly appreciated.

Birken Vogt · May 25, 2019

OVERTORQUED said:
Hi all- been a little while. Does anyone know of any place open in and around East Bay, CA that I can find air brake chambers? NAPA doesn’t stock anything around here and my searches on web aren’t coming up with anything. Big rigs don’t stop running, so they have to get them somewhere right? Any info greatly appreciated.

I have no idea on the management of these stores but Fleetpride is a national chain and a lot of different sources point to Dentoni.

https://branches.fleetpride.com/ca/concord/truckparts-con.html
https://www.dentoni.com/

Tinkerer · May 25, 2019

Any heavy truck repair shop should have what you need. Take your Case chamber to them and they will match it up for you. I think you need a type 30 chamber. Better known as a 30/30 chamber. Napa should have them in stock.
You will most likely never find an identical chamber like your OEM Case one.
I think the last time I bought a pair they were $75.00 a piece.
You will have to carefully cut the rod to the correct length.
This an example of what you prolly need. ---->https://www.amazon.com/AIR-BRAKE-CHAMBER-30-SEALED/dp/B07581B5PV
At the bottom of the Amazon page are several sources for them.

OVERTORQUED · May 26, 2019

Tinkerer said:
Any heavy truck repair shop should have what you need. Take your Case chamber to them and they will match it up for you. I think you need a type 30 chamber. Better known as a 30/30 chamber. Napa should have them in stock.
You will most likely never find an identical chamber like your OEM Case one.
I think the last time I bought a pair they were $75.00 a piece.
You will have to carefully cut the rod to the correct length.
This an example of what you prolly need. ---->https://www.amazon.com/AIR-BRAKE-CHAMBER-30-SEALED/dp/B07581B5PV
At the bottom of the Amazon page are several sources for them.

Question for you... currently has 24/30 on it now and even with good brakes adj. correctly, it doesn’t ever really want to stop well. Pressure is above 100 lbs. If I change to 30/30, will that give me any better stopping power?

OVERTORQUED · May 26, 2019

Birken Vogt said:
I have no idea on the management of these stores but Fleetpride is a national chain and a lot of different sources point to Dentoni.

https://branches.fleetpride.com/ca/concord/truckparts-con.html
https://www.dentoni.com/

Fleetpride is awesome, but unfortunately it’s a holiday weekend so I guess I just have to wait til Tuesday.

92U 3406 · May 26, 2019

Likely not. The last number refers to the service chamber IIRC. It'd just have a larger park spring in a 3030 I think.

OVERTORQUED · May 26, 2019

Ok, wasn’t quite sure. Any ideas on trying to stop this big heifer better? Replaced both treadle valves already. Maybe the new air chambers will make a difference- the shoes still look good and they have been adjusted up. Maybe shoes are glazed?

funwithfuel · May 26, 2019

OVERTORQUED said:
Ok, wasn’t quite sure. Any ideas on trying to stop this big heifer better? Replaced both treadle valves already. Maybe the new air chambers will make a difference- the shoes still look good and they have been adjusted up. Maybe shoes are glazed?

Did someone maybe get carried away greasing the cam bushings? Get a little grease on the shoes? Wheel seals ok? No leaks. How is the braking performance in general, smooth and straight, or pulling one side over the other. Do your treadle valves have the same crack pressure and distribution rate as OEM? How bout the relay valves, or does it even have them?

OVERTORQUED · May 26, 2019

funwithfuel said:
Did someone maybe get carried away greasing the cam bushings? Get a little grease on the shoes? Wheel seals ok? No leaks. How is the braking performance in general, smooth and straight, or pulling one side over the other. Do your treadle valves have the same crack pressure and distribution rate as OEM? How bout the relay valves, or does it even have them?

On treadle valves I crossed the part number to a BENDIX valve- as far as pressure and distribution rate- I don’t know. The braking performance in general... well it’s not really smooth but it’s straight. No pulling. I will check shoes and wheel seals again, but everything looked good before. Relay valves- that I don’t know either. Could you expand a little for me?

funwithfuel · May 26, 2019

I'm just speaking in broad generalizations. Most often the treadle will actuate a relay valve which acts on the service brake. If those are chalked up inside or worse yet, gummed up, they could cause you grief.

OVERTORQUED · May 26, 2019

Really appreciate the info/input. I’m going to run through everything again to double check. Tuesday I will get the chambers, install those and see if there are any improvements. Thanks so much!

Tinkerer · May 26, 2019

My 680 will slide the tires when I mash down on the pedals hard. Dirt or asphalt doesn't matter which.
Can you hear air hissing when you apply the brakes ?
Are the slack adjusters all the way to the end of their travel when you apply the brakes ?
Do the brakes hold good when the parking valve has them locked ?

OVERTORQUED · May 28, 2019

Tinkerer said:
My 680 will slide the tires when I mash down on the pedals hard. Dirt or asphalt doesn't matter which.
Can you hear air hissing when you apply the brakes ?
Are the slack adjusters all the way to the end of their travel when you apply the brakes ?
Do the brakes hold good when the parking valve has them locked ?

Took another look and one of the air chambers was leaking so we went ahead and decided to replace both of them. On another note... Who in the sam hill designed these treadle valves/foot pedal? I didnt have the good fortune of replacing the last one-you want to talk about testing your patience skills to get those bolts out? Lol! Appreciate all the help from you guys.

Tinkerer · May 29, 2019

If the pedal pivot-pin is frozen in place, there is a way to make life way easier when removing the treadle valves. Carefully determine the location of the LH pedal pivot pin on the outside of the cab. Then drill about a 3/4 inch hole in the cab. That will create a hole that you can insert a punch to drive both the LH and RH pedal pins out.
Once the pedal is removed those dam bolts under it are super easy to remove.

OVERTORQUED · Jun 3, 2019

Tinkerer said:
If the pedal pivot-pin is frozen in place, there is a way to make life way easier when removing the treadle valves. Carefully determine the location of the LH pedal pivot pin on the outside of the cab. Then drill about a 3/4 inch hole in the cab. That will create a hole that you can insert a punch to drive both the LH and RH pedal pins out.
Once the pedal is removed those dam bolts under it are super easy to remove.

Hahhaaaa- wish id of read that earlier... My phone wasnt working. Oh yes, the pin was frozen. Didnt want to crack anything beating that pin out so did it the hard way. I will remember that next time though, thanks.

680H Air Brake Chamber question...

OVERTORQUED

Well-Known Member

Birken Vogt

Charter Member

Tinkerer

Senior Member

OVERTORQUED

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OVERTORQUED

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92U 3406

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OVERTORQUED

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funwithfuel

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OVERTORQUED

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funwithfuel

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OVERTORQUED

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Tinkerer

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OVERTORQUED

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Tinkerer

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OVERTORQUED

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