12 or 24 volts?

[jwc9]

Ok this may sound crazy but I have been arguing this with some co-workers and I want to be sure I am correct. They are telling me all diesel pickups use 24 volts on the starter to run. I do not believe this since the batteries would have to be wired different than they are on all dodge chevy and ford trucks. What do you guys have to say?

 

[Gary - K7GLD]

They are full of it! Probabaly some of the same "Ford owns Cummings" bunch that continually spread lots of other similar nonsense... :-laf:-laf

 

[fkovalski]

2 batteries wired in parralel. 12v with 2x the current.

 

[jwc9]

Thanks guys!

 

[fkovalski]

Also...



Suppose this: What if you were to jump another vehicle if your truck's batts were wired to be 24V... you would spin the other cars starter REALLY fast! Conversly... no other 12V car would be able to jump your truck.

 

[Jefff929]

I used to work on GMC bus coaches that were wired to give the starter 24v and the coach itself 12v. They don't do that on pickups.

 

[JBonpua]

I have a (Japanese only) Toyota Land Cruiser with a Hino 4. 2 Turbo Diesel. It has two battery wired in series but it has some kind of relay attached to one of the battery to the starter where the starter is 24V but the rest of the electrical is 12V. All local Japanese diesels that I've seen when I lived in Japan for 19 years (just moved back to CA Jan 07),with 6 cylinders or more will have 24V starters.

 

[Hoefler]

I have a (Japanese only) Toyota Land Cruiser with a Hino 4. 2 Turbo Diesel. It has two battery wired in series but it has some kind of relay attached to one of the battery to the starter where the starter is 24V but the rest of the electrical is 12V. All local Japanese diesels that I've seen when I lived in Japan for 19 years (just moved back to CA Jan 07),with 6 cylinders or more will have 24V starters.

That is a parallel switch. Switches the batteries from parallel ( 12v ) to series ( 24v ) for starting. Allows for a 12 volt charging/running system and 24 volt starting system. Many road trucks have them.

 

[Gary - K7GLD]

WELL, we might be getting a bit off track here - sure, there are SOME random and scattered examples of 12/24 systems - but the basic question here as I understand it is, do the current dual battery setups in our domestic trucks (Ford, Dodge, GM) switch between 12/24 volts when in the start mode?



And THAT reply, is still a definite no!

 

[JBonpua]

That is a parallel switch. Switches the batteries from parallel ( 12v ) to series ( 24v ) for starting. Allows for a 12 volt charging/running system and 24 volt starting system. Many road trucks have them.

Hoefler, thanks for the insight on this switch. I was wondering how it is done. I knew the electrical is 12V and I could see a label on the starter says 24V but I did not know how it was done, seems like magic to me. I also have a Nissan Patrol with a UD 4. 2 Diesel and it has two bateries as well but it is wires in series so everything electrical is 24V. Got lo love all the diesels in OUR STABLE. Oh I forgot I also have a Beetle TDI but my favorate of couse is my 3500 Mega Cab CTD.

 

[AKaiser]

All NATO standard equipment is 24V, I know that. I think most really large equipment is 24V. I think most all farm equipment and OTR trucks in the US are still 12 Volt.

 

[fkovalski]

Not to hijack... but sorta' on topic:

Do the LARGER semi trucks with on- board compressors use "air starters?"

 

[Simplysmn]

The only trucks I have seen with a true 24 volt system is the Military all there jeeps and trucks aare all 24volt even the humvee's and the duce's run 24 due to all there radio Equipt is 24 volt . and yes the big class 8 trucks atleast use to have air starters on them dont know if the new one's still do .

 

[MMichaels]

RE: air starters

I recently saw- or, rather, heard - a new Freightliner with an air starter, so they apparently are still available. What a great way to wake up your neighbors!

 

[chuckwilson]

Only big fleets use air starters, they are still out there, but if your tank leaks off you had to get another truck to pump it up, & you only get 20 seconds of good cranking. they are kind going away just like Consolidated Freightways did!!!!!!!