i am going to be purchasing a (new) used Dodge/Cummins truck within the next year, so i kind of need some info.
thanks in advance.

which cummins engine should i go with, the 12 or 24 valve engine.
i have heard of a timing pin falling out and causeing damage to the 12 valve engine, is this true? also, the 24 valve engine seems to have fuel/lift pump problems, is this true?

and in the area of trannies i prefer a manual, which is better the 5 or 6 speed?

which engine is cheaper/easier to modify?

are there any other problems that i am unaware of? thanks.

 

The KDP is an issue with 12 valves and early 24 valves. The fuel system on the 24 valve trucks has been more trouble prone, but most run fine. With a 12 valve you can have a 5 speed or a 5 speed, whichever you prefer. The 24 valve HO trucks came with the 6 speed, it is a stronger unit with closer gear ratios. Some have complained that it's hard to shift. The 12 valve is cheaper to modify, but the 24 valve is easier for mild gains - you just plug in a box for 40 HP or so. You seem to have heard about all the big problems.

 

Cajun Diesel, Just keep reading the post on this site and you will get the answers to most or all your questions. Hope you find your dream truck. good luck

Gene 007
WarWagon

 

IMo having owned both. the 12V is hands down the better engine overall.If you can find a clean one that fits your needs id jump on it

 

The only bad thing is that you could only get a quad cab for 1/2 a year with a 12 valve. So if you need a quad cab that kind of narrows down your search if you want both.

 

I'd do the twelve valve. I've had both. My son has my 12V now at 240K. He's replaced the mechanical fuel pump once and one relay
to the fuel shut down. The Auto Tranny was done at 118K. Thats it. The HP is down from the 24Valve, but that can be fixed easily.

Best truck I ever had on the road. Could run from Canal St in Nawlins to Melbourne, Florida without stopping for fuel.

The 24Valve just has to many sensors, fuel pump problems which lead to injection pump problems sooner or later. One kinda goes with the other. That electronic fuel injection pump is high dollar stuff. The injection pump on the 12 Valve is almost bullet proof.

So I guess, if you want reliability go with the 12Valve. If you the newer stuff, find a common rail 5.9 without the common injection pump.

In any case, you be a Gone Pe'Caun.

Dave

 

If it came to a third truck, I would look for a 12V although I have never owned one.

The salesman actually convinced me to wait for the "new" 24V and I bought a 1999 QC SB 4x4 5sp and was pretty happy with it after switching the 275 injectors with a 3 button Edge.

In 2002, I looked for about 4 months and could not find a nice 94-98 12V with less than a 100K for less than 15K dollars. I finally decided I wanted the QC more than the 12V and bought my 2001.5. I like it better than the 1999 if not for the rear disc brakes alone. This truck won't track straight just like my 1999 though.

I would trade my 2001.5 even up for a 98.5, QC SB 4x2 5spd 12V with the same mileage and overall condition any day of the week. I really don't need a 4x4 and have a Jeep.

What convinced me was a ride in a similar truck last year. It was an ST model with the durable cloth seats, 370 hp Diamond (P)? injectors, GSK and a plate which I believe was a 10 or 11 but could be mistaken. That truck was a total sleeper, it would have stomped my 99 in the dirt and it was smooth on the highway too

 

I have had both and I like my 24v much more. I love the 6 speed. I havent had any major problems with either. I guess it just depends on what you're gonna do w/ the truck and if you are your own warrenty.

If you do decide to go w/ a 24v, btwn the the yrs of 99-01, make sure to check to see if it has a 53 block. Some of these blocks have cracked. Also, the later 01.5's have disk brakes all around, making braking much easier for the driver.

Which ever you decide, it will be a good choice...its a CUMMINS!!!

 

Wannadiesel said,"with a 12 valve you could have a 5 speed or a 5 speed. I have a 92 12 valve with a 6 speed. The truth is the 6 speed is tough. but when you start making serious power than you dont need the close ratio of the 6 speed, 5 is plenty.
If you like to tinker, than the 12 valve is the way to go, if you want to drive a nice quiet truck and want power than buy a 24 valve and plug in a box and go.
The sky is the limit with these trucks and some imagination.
Good luck

 

CajunDiesel:

I currently own both a 96' Dodge CTD 12 valve and a 2002
Dodge CTD 24 valve. I agree 100% with "John D." and
"CoastalDav" that the 12 valve engines are much more
reliable! Personally, I have had a fair amount of trouble
with the fuel system on my 2002 and so have alot of
DTR members. IMO, the fuel system on the 24 valve
Cummins Engines is barely adequate even in stock
condition. I have had three (3) lift pumps fail on my
2002 and the truck only has 40,000 miles on it!!!
My 96' 12 valve has 240,000 miles and the fuel system
on that truck has NEVER given me any problems!!
I believe the P7100 Bosch Fuel Pump on the 12 valve
engines is very, very TOUGH and RELIABLE!! For one
thing they are cooled by BOTH fuel and oil, where the
VP-44 (24 valve fuel pump) is cooled only by fuel.
If you look at them side-by-side you can see what
I am talking about.

Anyway, good luck to you on whatever you decide.

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John_P