Possible solution for dreaded engine stall when brakes are locked up.

Oops. Beer goggle posting. Wrong thread, fixed.

ABS MWO Kit arrived today. One heavy kit!

mdainsd said:

wow, so negative.

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Naw man just a mechanic that sees how engineers screw things up constantly, and you will need much thicker skin if you thought that was negative.

74M35A2 said:

I’m not an engineer, I work at the bowling alley. Davis is a good guy. I just drive him, and most others, nuts sometimes.

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Yeah you are just the shoe smeller and ball licker at the bowling alley! Get to twisting wrenches discoball! I would like to at least see you put in the rear window this year.

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"Shoe smeller" was classy (from on oyster eater), and then the bomb bay doors opened.....

News flash abs or not if your converter is in lock up and you slam the brakes fast enough your going to kill the engine I have seen it done several times on ice and had it happen to me once. It is almost impossible to do it on asphalt by the time the brakes have generated enough friction to lock the tires the converter has un locked. The other thing to remember , if you are driving an Allison in slick conditions ,once you lock the tires the trans will shift back to low gear, and there wont be enough resistance to get it to upshift, one has to momentarly accelerate to get the trans to up shift regain control.

simp5782 said:

The OP wasnt referring to a broken transmission. His thread was in relation to the military mwo to add abs to the trucks. The engine stalled and steering is lost when the brakes locked up stalling the whole driveline. Hint as to why your truck has abs

https://youtu.be/PvW9ISZ6LlM

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Being unfamiliar driving these trucks I don't get how they can roll while driving as the video says. How are these trucks rolling over? Does the truck go in a skid sideways and once sideways enough it rolls over?

Simple enough. Many people who collect these trucks have tons of experience on how to handle such a beast. Flip the coin over and you'll find Soldiers of any kind of background. I've met some who never had a driver's license in their life but now operate big trucks. The M939 series trucks biggest flaw was possibly the automatic transmission. So easy, anybody can drive one! Prior to that, you had to know what a clutch pedal was and how it was used in a medium series truck. I always treat mine as if it's the most dangerous thing on the road, give myself plenty of time to brake and so far have kept everyone safe. My youngest son even hangs onto the bar in front of the dashboard while underway.

sandcobra164 said:

Simple enough. Many people who collect these trucks have tons of experience on how to handle such a beast. Flip the coin over and you'll find Soldiers of any kind of background. I've met some who never had a driver's license in their life but now operate big trucks. The M939 series trucks biggest flaw was possibly the automatic transmission. So easy, anybody can drive one! Prior to that, you had to know what a clutch pedal was and how it was used in a medium series truck. I always treat mine as if it's the most dangerous thing on the road, give myself plenty of time to brake and so far have kept everyone safe. My youngest son even hangs onto the bar in front of the dashboard while underway.

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How are you keeping your truck from rolling over?

Nomadic said:

How are you keeping your truck from rolling over?

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Driving as responsibly as possible and avoiding panic braking scenarios. I have also familiarized myself with how the truck feels under threshold braking on quiet country roads. Through this I learned to lower my rear tire air pressure from the 70 psi called for in the technical manual down to 35 psi when running unloaded. Prior to lowering the air pressure the rears would chirp under hard braking which is indicative of the ABS module attempting to keep the truck from locking the rear wheels completely. Now with the air pressure lowered in the rears, it stops hard and evenly when needed. It's a good exercise to try in a remote area. I mostly stick to my first rule though, drive responsible and avoid panic brake scenarios. I constantly scan traffic ahead and around me, something my Dad really instilled in me once I started riding motorcycles. Treat all traffic as if it's going to do exactly what you don't want it to and have a plan to react. It's not a 100% solution but it certainly helps.

Roll this over to this thread since it pertains to it. Gives a detailed written description of the ABS problem.

https://www.globalsecurity.org/military/systems/ground/m939.htm