mud and snow switch ?
 

My 2003 T-600 has a mud and snow toggle switch ! When push up on the switch and let go, it returns to its original position. Can any one explain how this mud and snow switch works or what this is for and how it functions ? Or how and why i would use it?

I'm guessing that it's for a traction control system. Best bet - ask the guys in your shop.

Differential Lock
 

"mud and snow switch" Interesting. "what this is for" Locks the axle(s) differential. "how it functions? Mechanically locks the differential so there's no wheel spin when one set of tires loses traction. Think solid axle, "posi-traction". "how and why i would use it?" Use it only when starting from a dead stop on slick surfaces and you don't want to lose traction. Never on a highway, never in a turn, and never in higher gears. That's how a shop bubba explained it to me, never used it. BOL

Thanks OTG, "power divider" that's what I thought he meant. Learn something everyday. ;o)

Re: Differential Lock
 

Actually, the "mud&snow" switch activates the anit-lock braking system, when it is held up. It makes the brakes work in the same fashion as they do when you slam on the brakes in an emergency, with the theory that you will be able to pull out of a "spin out", instead of becoming stuck. I always found that it is best to just flip on the power dividers, grap a higher gear and lug my way out of a "spin out" situation. That friggin little "mud & snow" switch will bleed the air pressure off in a hurry.

Sealord...the switch you are refering to is the "inter-axle" lockout switch, which does exactly what you described. The deal with it is, you must have the differential's power divider already locked in before activating the axle locker's, or you will blow a differential quick. Using the axle locker makes turning 90 degree corners and yard manuvering tough...the truck tends to start bunny hopping because of the lack of freedom in the axles as they are working.

Re: Differential Lock
 

So I take it the mud and snow switch is pretty much useless !

Re: Differential Lock
 

It's not totally useless.
It does help if your on a grade and have to maintain power, and you start spinning the drivers...and you don't already have the power divider engaged. If you manage the switch right, you can activate it in bursts, and get yourself out of a pickle...but you have to pay attention to your air gauges.
Because it does activate the anti-lock braking system (which means your drive-axle brakes are activating one wheel at a time, very quickly) it bleeds the air down just as quickly as the brakes activate..which can be quick. Getting out of a pickle without losing forward momentum is one thing...locking your brakes up while in motion because you lost all the air...presents new problems.

It's best to have the power divider already engaged, if you feel the roads are to slick with snow or rain, and you have to pull a steep grade. I'm not talking grades as in mountian driving...but rather the types of grades you will run into doing city deliveries. Usually with speeds of 40 mph and less. You do not want to activate the "mud & snow" switch at speeds over 40 mph. Under 25 mph is best.

Ha. So much for a company going over a truck and its equipment with a driver before sending them out.

Once you drove one truck you drivin them all.

Really? So a driver who's only ever been in an automatic can jump in an old Mack with a 5 and 4 tranny and drive it with no instruction? Hell, when I switched from my 2002 Volvo to the 2005 Volvo, I had to ask the guys in the shop what a couple of the switches were for because the way they were marked.

No - all trucks aren't the same.

You got a point. But i was talking about going to one stick truck to another. I keep forgetting you can get atuos in big trucks.