6x6 performance upgrade question

[DDoyle]

As I contemplate work on a six-by - a question comes to mind.....

On more than one occassion I've longed for faster-stopping brakes on my bone-stock five-ton.

Anybody here made any mods to this system that resulted in reduced stopping distance?

Anyone added a dual-circuit system to a five-ton, or adapted a ABS system to one?

Best wishes,
David Doyle

 

[98hd]

As I contemplate work on a six-by - a question comes to mind.....

On more than one occassion I've longed for faster-stopping brakes on my bone-stock five-ton.

Anybody here made any mods to this system that resulted in reduced stopping distance?

Anyone added a dual-circuit system to a five-ton, or adapted a ABS system to one?

Best wishes,
David Doyle

I thought there was a company TNJ maybe? that does air brake conversions. I think it would be a great addition, if not too expensive.

 

[Stretch44875]

Are there civilian applications for the 5 ton axles? I've seen rockwell double reductions under garbage trucks and dump trucks, that are air braked. Maybe swap the backing plates and mounting hardware over, and go to full air brakes.

Dennis

 

[WillWagner]

David, I think adding ABS to a system on theses trucks would be like reinventing the wheel. There are pick-ups, tone wheels, computers, new master cyls, pedals and more involved. Lotsa time, money and labor involved. Air braked ...just regular old s cam brakes...would be great. Too bad there is nothing available for the 2.5 ton trucks!

 

[southdave]

clark truck sale and do conversion to straight air brakes for five tons love to do one for 2.5 but all say it is possible

 

[jeli]

Air brakes. The 929 I used to drive didn't have brake issues but tire issues. If it would have had street radials it would have stopped on a dime.

 

[OPCOM]

The national guard in TX has added ABS to the rear wheels of the current 5T trucks. It helps prevent getting sideways and rolling when the truck is empty. The kit is based on a trailer kit of all things.

 

[Jakob]

If it works, use it...

I'd like better brakes for my deuce as well. I don't know enough about air brakes to even think about modifying the system for that though.

 

[cleb]

I think I have seen pinion brakes on the rockwell axles. Can those be added to a deuce with the stock brake system? Seems like if you did one on the rear most axle and the front it would help a bit.

 

[rosco]

The design for these trucks is 30 plus years old. Its principal use/design was Off-Highway, with some Highway capacity. If the brakes are maintained, and adjusted up properly, they preform as designed. Applying todays standards in terms of speed and performance is questionable. Modifying the existing systems would also add substantial liability. Few are qualified to do such work!

Lee in Alaska

 

[Jakob]

I think I have seen pinion brakes on the rockwell axles. Can those be added to a deuce with the stock brake system? Seems like if you did one on the rear most axle and the front it would help a bit.

You've seen them and other than a custom bracket, they use off the shelp brake parts. I believe it's a Toyota truck rotor and a Mazda truck caliper... or maybe reverse that. I don't know how well they'd slow down this heavy of a truck though. That brake setup is intended to be used on buggy and "light truck" applications.

 

[cranetruck]

Before considering "pinion" brakes, please read up on them, they work via the differentials and are not suitable as service brakes.

The 260-20 manual (M809 5-tonners) states that the braking performance should be:
"Distance required to stop at 20 mph is 21.9 feet at 200 psi max pedal pressure."

How close to this are you, David?

Bleeding the system correctly is also a big consideration, I have had the best, by far, results by using the "insect sprayer" method suggested by Kenny. Any air bubble in the lines will give you less than max performance.
Hydraulic lines should be acting like a solid linkage, the fluid is non compressible and any mushyiness whatsoever indicates air.

 

[hndrsonj]

I have seen a white 5T dump in north texas that had the civilian style air brakes. Don't know where they came from though.

 

[Jake0147]

I think I have seen pinion brakes on the rockwell axles. Can those be added to a deuce with the stock brake system? Seems like if you did one on the rear most axle and the front it would help a bit.

You've seen them and other than a custom bracket, they use off the shelp brake parts. I believe it's a Toyota truck rotor and a Mazda truck caliper... or maybe reverse that. I don't know how well they'd slow down this heavy of a truck though. That brake setup is intended to be used on buggy and "light truck" applications.

That setup will overheat the (crap) out of the brake caliper if one front and one rear are used at speed to stop a six to seven thousand pound mud truck. Two or three times as heavy means two or three times as much heat.
That setup also wrecks pinion bearings very quickly, I'm assuming from a side load from a place and direction it was not intended, or possibly in the correct direction but at more forcable levels than anticipated. Not 100 percent sure why on that one, but this according to the four by four club guys, axles with brakes eat bearings and axles without them don't.

 

[gimpyrobb]

I think I have seen pinion brakes on the rockwell axles. Can those be added to a deuce with the stock brake system? Seems like if you did one on the rear most axle and the front it would help a bit.

You've seen them and other than a custom bracket, they use off the shelp brake parts. I believe it's a Toyota truck rotor and a Mazda truck caliper... or maybe reverse that. I don't know how well they'd slow down this heavy of a truck though. That brake setup is intended to be used on buggy and "light truck" applications.

That setup will overheat the (crap) out of the brake caliper if one front and one rear are used at speed to stop a six to seven thousand pound mud truck. Two or three times as heavy means two or three times as much heat.
That setup also wrecks pinion bearings very quickly, I'm assuming from a side load from a place and direction it was not intended, or possibly in the correct direction but at more forcable levels than anticipated. Not 100 percent sure why on that one, but this according to the four by four club guys, axles with brakes eat bearings and axles without them don't.

The bearings probably go from the heat. Those puppys are spining 6.71 times faster than the axles are turning. Remeber the gear ratio.

 

[imported_Squirt-Truck]

David,
Will your 5-t not lock the wheels? There is sufficient brake application with a properly operating stock system to lock the wheels at full load. Locked brakes is all that can be expected from a brake system. Air brakes are no better than locked, and yes drums are superior to disk in stopping ability for the same line perssures. Tires are the critical element in stopping distance. We do brake performance testing at work, if anyone wants to pony up differing tires we will test and verify what does what. FYI, typical passenger car/truck tires give roughly a 0.70g stopping coeff. Heavy truck tires get about a 0.50 coeff.

 

[Offroadfabworks]

Do not run pinions on a deuce thats on the street. Heck dont run pinions on a street truck period. pinion brakes are used on offroad only for slow speeds..

We make disk brake conversions for 2 1/2 and 5 tons and can get them with a 6 piston caliper if needed. but i dont know how the system will act with the weight of a 5 ton in stock form. thats a heavy truck. Plus ABS is possible but i dont know the benefits or justifiable (sp) on a 30+ yr old truck

 

[DDoyle]

David,
Will your 5-t not lock the wheels? There is sufficient brake application with a properly operating stock system to lock the wheels at full load. Locked brakes is all that can be expected from a brake system. Air brakes are no better than locked, and yes drums are superior to disk in stopping ability for the same line perssures. Tires are the critical element in stopping distance. We do brake performance testing at work, if anyone wants to pony up differing tires we will test and verify what does what. FYI, typical passenger car/truck tires give roughly a 0.70g stopping coeff. Heavy truck tires get about a 0.50 coeff.

No, but since it is a M62 and considerably outweighs most of the other five tons, I'm not surprised by this.

DD

 

[m-35tom]

my deuce with power steering, greatly improved brakes and high overdrive will be at aberdeen. come drive it. it will throw you through the windshield it stops so fast.
tom

 

[imported_Squirt-Truck]

David,
Sounds like you have a brake system problem. I do no know the weight of an M-62, but Lil-Squirt will lock all ten at 47,950# on typical asphault. And, yes M-35tom they will make you feel that you are going through the windshield..