View Full Version : dodge 12 valve diesel

03-25-2007, 09:31 PM
how do hey compare to the 24 valve?

03-25-2007, 09:32 PM
they have half as many valves

03-25-2007, 09:37 PM
A bit more reliable, I have heard. But not as powerful.

03-25-2007, 09:45 PM
rich and rick will be able to give ya some good input.

the 12v is mechanical and is more of a bolt on type upgrade, where the 24 is more chip type upgrades.

both are great motors.

03-25-2007, 09:48 PM
looking for a diesel, and i love dodge.

what abou ttowing?

FU Toolbag
03-25-2007, 09:52 PM
My dad loves his, except it's dying. Not cheap to rebuild, but very strong and reliable.

03-25-2007, 10:07 PM
whats the expected life expectancy of these 12 valves

03-25-2007, 10:09 PM
I think T-O has a 12 valve but I could be wrong ask him

03-25-2007, 10:29 PM
One of the macninists at my work has a one with 700k on it. great fuel economy and really reliable.

03-25-2007, 10:38 PM
whats the expected life expectancy of these 12 valves

Like anything it depends on how well it was maintained. There are several reports from RV haulers and hot shot drivers that have over a million miles on them.

If your concerned about the motor take it into cummins in port kells and have them run it on the dyno. They will be able to tell by the blowby wether it needs a ring job or not.

Watch out for the "53 block" that was a series of castings that were known to crack and cause a coolant leak. there would be a 53 cast on the block somewhere.

The next thing is the "killer dowel pin" there is a pin in the timing gear cover someplace that can work loose and drop into the gears. This will blow holes in the front cover causing a major oil leak.

"93 (94?) lift pumps and later are known to be weak. these would be an electric one that sits on the rail or in the tank. '93 and earlier had a diafram pump that ran off the cam on the engine.

03-25-2007, 10:58 PM
the 12 valves are a good motor...great milage out of them..cant chip them everything you need to know if on this site http://www.dieseltruckresource.com/dev/index.php the 24 valves dont need to worry about the 53 block

03-26-2007, 01:53 AM
Bought main last year and love it...90 with a 12 valve, and no intercooler. Never left me stranded.wouldn't mine the intercooler though, these trucks just run forever with descent maintainance...

03-26-2007, 08:26 AM
89-93 12v had the VE rotary injection pump, the pump can still turn out decent power but nothing compared to the bosch p7100 inline pumps off the 94-98.5 12vs. The 1st gen trucks started becoming intercooled in 92 but some very late 91's had it.The getrag 360s that came being the 1st gens where good but if you lugged the truck at all then they began to have issues, other good transmissions that sometimes get a bad rap.

The 2nd gens are better engines because they flow a bit more fuel, the HP rating increased yearly until finally 215HP on the 98 12vs. The engines go good stock, and the nv4500 backing them is awesome.

The engines are very reliable, but do require the typical maintanance to get the durability. The stories of trucks lasting 700k arent bullshit, but are usually single owner people who understand and are very stringent on maintanance. The front ends on these truck arent perfect, the cummins is a heavy engine and the front ends wear of fasting due to this. The 1st gens have kingpin 60 in the front, but the 2nd gens have a CAD( Central axle disconnect) that sucks and these axles have unit bearings where are not fun.

And no matter what, run a good additive to your fuel. ULSD is very abrasive compared to LSD which had better lubrication properties.

If you find a nice 12v, i'd pay the 100 bucks and bring it into piers and get them to go through it. When i was looking at 12vs, they checked: fuel pressure, boost,turbo play, oil pressure and they took it for a good test drive. Their mechanics there are nothing short of genuiuses, they can tell a fair bit from driving it.

Looking for 2wd or 4x4? These trucks are awesome

03-26-2007, 08:51 AM
gots a 98 12 vavle, love the fukin thing, needs a bit more juice to her but she pulls like a mother fu*#er. ive put her thru her paces off road aswell and she performs quit well for a lawn dart. ive several 24 vavlve that im able to drive from time to time and man their sweet, one of them is totaly tricked right out to the point where he plugs his phone in to his truck ....blammo instant crazyiness.i notice his is gettin bagged on quicker than the others too. but that 12 valve of mine hasnt changed pitch, has run the same since the day i got it and i bought it to tow a 30 ft 5thwheel, yup all i say is i am very happy with this truck.hmmm im goin for a drive.

03-26-2007, 08:39 PM
98 12vs are ballsy, but a stock 12v does pull well.

03-26-2007, 08:54 PM
my tow rig is a 02 dodge 6 speed pulls well on 35s soon will be puttin edge on it.drove the drumax for 2weeks trany and frame sucks i'am a chev guy broght dodge havent look back.[36]

sj-x 500
03-26-2007, 09:51 PM
i've got a plane jane 01 auto 5.9, just did the 4 inch exhaust, before that it still kicked ass for towin shit around. hauled a full size bronco up from winfeild to westbank only crappy part was gettin cut off before the hill, kinda sucked hind teat after that one

FU Toolbag
03-26-2007, 10:04 PM
My dad has a "spare" 12 valve that he got to replace his worn out 12v. The new one has 900,000kms on it. He swore it would need a rebuild, you can still; see the crosshatches in the cylinder walls.

03-26-2007, 11:19 PM
I think T-O has a 12 valve but I could be wrong ask him

I do have one, And its not for sale...
That should answer any questions you may have.:D

12-15-2007, 11:31 PM
if you wanna make big power 12v's are the way to go, twins+P7100=broken drivetrains[cheers]

12-17-2007, 02:09 PM
12 valves can be built to higher powers and withstand it better than a 24V

If you're just gonna keep it fairly stock for a tow rig, then either will do you fine. 24V being quicker to upgrade by just plugging in a chip. But 12V's can be bumped up pretty easily too.