Engine/Transmission (1994 - 1998) Known 12 valve issues. What are they.

[Sticks]

A buddy of mine just bought a used 97 2500 Auto, 4x4. I have told him about the KDP issue, and that he needs to see if it has been addressed, and that the fuel filter is not a pleasant thing to change. What else does he need to know about his new toy.



He will be using it to tow a 5000# trailer (race car) in Colorado - mountains included. I told him that he should get an aftermarket air filter (AFE or BAHF), and dump the muffler to help keep the EGT's down. Also to get at least a trans temp and EGT gauge.



As far as we both know, the truck is STOCK. Is there cheap HP available for it? Edge EZ, Injectors, ?Fuel Plate?

 

[Texas Diesel]

Lose the kitty, tap the AFC housing full forward, rotate the Star wheel inside the AFC housing til smoke or EGT says stop. Losing the CAT converter will be a BIG help. Watch the exhaust manifold, per Mr Donnelly, the ends will shrink and break off the mounting bolts, when the manifold "ears" touich the bolts replace the manifold.

 

[Deezul1]

After installing a EGT gauge, contact TST for a #11 plate. This will make a nice difference in power and when that starts to feel like more is needed (and it will) then go for 370 injectors. See my sig below for results of this setup.



Oops #11 not the best for an auto trans, check TST website for plate specs

 

[Jim Fulmer]

Don't know how a #11 will work with an automatic but a #10 works real nice, power comes on a little later in the band when the R's are up and it has a nice moon shaped fuel curve, Call Piers's shop if you want to ask another person 1-866-888-9396.



Jim

 

[Sticks]

Originally posted by Tejas Deezul

Lose the kitty, tap the AFC housing full forward, rotate the Star wheel inside the AFC housing til smoke or EGT says stop. Losing the CAT converter will be a BIG help. Watch the exhaust manifold, per Mr Donnelly, the ends will shrink and break off the mounting bolts, when the manifold "ears" touich the bolts replace the manifold.

whaa... .



You are talking to a over-valved owner here, and he will be relaying the info to a newbie.



Kitty = catalytic converter. I got that, but I don't know if the truck has one. Oops, 97 yes it probably does, they stopped in what, 2000. The truck has to stay legal.



AFC Housing = ??? Star wheel??? Is there a link to the procedure for this? Sounds like a twist here for more power thing, no parts needed.



Thanks for the replies everyone, keep 'em coming. What about any other known issues. We 24v's have the lift pump and the typical Dodge steering. 12v's have the KDP and ... .

 

[Rams-n-Hogs]

We 24v's have the lift pump and the typical Dodge steering. 12v's have the KDP and ... .

the typical Dodge steering.



Jim

 

[#crnxr]

Here's my amateur understanding. . the 94-98 12V fueling is controlled mechanically. The AFC (Air/Fuel Control) module is where the fueling plate and star wheel are located. The profile of the cam plate determines the quantity and timing of fueling, while the star wheel dictates the quickness of fueling in relation to boost. Those more knowledgeable members please correct me if I'm off here.



More info regarding the fueling plates (cam plates) and other info. . .



http://www.tstproducts.com/



http://www.tstproducts.com/power_install.html



http://dodgeram.org/



http://dodgeram.org/tech/dsl/more_power/power_p7100.htm#tst_curves



There are a couple links regarding "Reported Problems" on the dodgeram.org page that should get your friend started. The throttle cable and linkage seem to be a common problem. There is also a side picture of the 12V Cummins with the critical parts labeled. If I find the link I'll post that too.



-Kyle

 

[zack_76401]

closing your wastegate will up wour boost... ... ... . or you can buy a non-wastegated turbo... ... ...

 

[Texas Diesel]

Originally posted by sticks

:

Kitty = catalytic converter. I got that, but I don't know if the truck has one. Oops, 97 yes it probably does, they stopped in what, 2000. The truck has to stay legal.



AFC Housing = ??? Star wheel??? Is there a link to the procedure for this? Sounds like a twist here for more power thing, no parts needed.

IF he must keep the kitty then atleast declaw it, cut the exhaust pipe an inch or so after the kitty, then let it hang down and use a long screwdriver and break the guts out, then get a exhaust coupling and two ubolts and put it back together. Done and the engine will be much happier, CAT's are the worst idea ever invented, EVERYTHING I own is kittyless.



AFC housing, better call me so I can explain, same with the Star wheel, PM me and I'll give you a number. Deezul 1 is really good with 12 valves, he could explain better than me.



Lots more power and no added parts

 

[zack_76401]

the TST book has step by step instructions on how to turn up the 12 valve and block the wastegate

 

[C. Harlan]

Block the wastegate.... Really good idea!

I did mine, put 191's in, and a week later, I had a grenaded HX35 after a 49 psi spoolup... . I would not advise fully plugging that thing... Unless, of course, you want a B1, H2E, or HX40/50... . get the adjustable boost elbow... . That will allow you to fine tune it, and stay in the effeciency range. Just thought you may want to keep that in mind.



-Chris-

 

[redram]

Guys,



He's pulling a race car. he needs a tow vehicle - not another race vehicle.

The 97 year is a good truck. Better if it was a 5 speed.

The auto trans is the weak link and adding a temp gauge to monitor fluid temp along with a auxillary inline filter to keep the fluid clean would be the first step. Eventually, if he ups the stock horsepower he can then upgrade the trans / torque converter.



Check for tight hose clamps on the intercooler connections.



Front end parts on the 4X4 along with the steering linkage are known weak links.



Throttle position sensor is a known problem.

Fuel lines (rubber lines from engine to frame) are a known problem.



Fuel sending unit problems in the fuel tank is a known problem.



Poor paint quality on the horizontal surfaces is a known problem.



Other than that, drive it and upgrade as desired.





Oo. Oo. Oo. Oo.

 

[Sticks]

Thanks to all for the input. I gave him the address of this site, and he had better be reading up on everything. I hope he has the sense to join up.



I looked over his rig, and it's very clean with 80k miles on it. I showed him the turbo boots to watch (including the bottom two - tears or cuts from the fender).



redram - Good point, it is a tow vehicle, but when has anyone ever said they had too much power?



He probably will need just enough to pull his toy over the mountain passes and be at or very near the speed limit, or at least have the umph to pass or get back up to speed.



I feel that when towing, I should be able to move around like I was trailer less and stock.

 

[redram]

Pulling a 5000 lb trailer, a stock Cummins should be more than adequate and act as if there is not a trailer hooked to it.



More than stock is not necessary to get excellent performance.

 

[Sticks]

Originally posted by redram

Pulling a 5000 lb trailer, a stock Cummins should be more than adequate and act as if there is not a trailer hooked to it.



More than stock is not necessary to get excellent performance.

25 miles of mountain driving on grades of up to 8% just to crest the first pass in a series of three leaving Denver going west... I beg to differ.



My first CTD was a 2001 2500 auto. I now have a 2002 ETH/DEE because the 01 could not even hold 50 mph on the aforementioned pass towing 3k#'s, whereas running empty, I could hold 70 mph with throttle to spare. Like it or not, our CTD's need to be enhanced a little bit to cope with the altitude, grade, and weight, or we have to be resigned to being the poor schlup in the right lane with the flashers on going 20 mph, making a career of getting somewhere. Maybe my first CTD had issues that needed to be addressed. That was not the only reason I switched to a manual, but by far the biggest, and the final coffin nail.

 

[redram]

I see your point - I haven't had that problem with an 89 5 speed stock pulling 10,000 lbs nor a 96 5 speed pulling the same load.



I also do not have to pull 8 percent grades.

However, as an engineer, I do not agree with building / modding a vehicle for the small percentage of time that you might be pulling that severe a grade when 99% of the time or greater you will not. Adjusting your mind to accept that you may only maintain 55 mph pulling a travel trailer up an 8% grade is alot less expensive.

Kind of like building a vehicle that will start and operate in Siberia in the middle of winter



However, if your 2001 auto could only maintain 20 mph, fix it. It was sick if you could not maintain 55 mph pulling 3000 lbs up 8% grade.



Glad you saw the light and got a manual.

 

[Pit Bull]

Known 12 valve issues. What are they. The trucks are around 5 years old or older

 

[LandShark]

Redram: Wow, a voice of reason on this site! I agree in keeping the mods to a minimum to keep your ride reliable and long lived.



Another thing to consider: It the truck has less than 100,000, it's under warranty and he may want to keep the warranty



Removing the muffler will get you a ticket in some places. If you don't go beyond a 230/605 plate, you can get by without the gauges and transmission mods (however: no racing, no burnouts, no driving like an idiot).



Also, redram's list on known problems is fairly complete. I would add checking the track bar, since it's a 4x4. If it's just a little worn, it will cause big driveablity problems.



Check with dealer to see that all recalls have been done.

 

[RedRamer]

I pull 6k lbs stock.

Learn to use the OD switch so that you don't overheat the transmission... I use OD off until I'm up to about 55mph then hit it. goes lockup to lockup 3 to 4th.

Learn to go easy in 2nd as that gear is the killer for heating up transmission. Get over it as soon as possible into 3rd lockup.

get a transmission temp sender in the out line and that tell you when it's hot.

Kitty, well I got 425k kms and it was looked at last year and it's as clean as can be. buy good fuel. Take it out if you plate it.

So far what I've done...

Fuel selenoid valve linkage - grease / oil it up, it eventually seazes.

KDP it.

Get good tires

Change oil/fileters regular

Get a fuel lift pump while you can cheap and keep it as spare. . it will eventually fo on you.

Get starter contacts keep as spare

Watch that transmission temp and enjoy the ride.

 

[Reddog1]

With an absolute stock truck, which mine is not, I recommend gages.



With a stock truck, buying one at a time, the following order:



1. Transmission temp gage and transmission line from a '95. You will discover your auto trans will get hot quick when backing up. You will learn to use neutral to cool the trans. Gage cost about $75, line about $120. Not cheap, but cheaper than a transmission.





2. EGT gage (rainbow type face). You will discover your exhaust temp will climb very fast in high elevations, especially if you are in the wrong gear. Cost is about $120.





3. Boost gage. Can indicate some intake problems. Nice to have but not really important (my opinion) in a stock truck.





I suggest the three gage "A" Pillar mount (about $65). You will be more attentive if the gages are eye level. If you only use the Temp and EGT gages, blank off the third gage.





I really believe that the trans temp and EGT gages are just about as important as the engine temp gage. This is especially true if you pull a trailer.





Wayne