Just recently bought an 06 Mega Cab 5.9 cummins. It has 190k and to the best of my knowledge is bone stock. Ill be using this truck to pull my 24ft enclosed trailer loaded down with my racecar and all the crap I take with me. I'm going to take a guess and say 9000lbs will be the total load I'm towing. (Just a rough estimate). Ok so now you know what I have and what I'm doing with it here comes the questions:

I want to add a programmer and some other bolt ons / plug and play type stuff. But I was advised to build my tranny first. I've noticed that the tranny shifts hard and sometimes feels like it double shifts. Like it will shift the same gear twice before throughly engaging into the gear. I've heard 2 different things about this issue. 1. That its the Valve Body & 2. That its a shift solenoid. I was doing some research and think I may want to upgrade the Valve Body to something more for towing. Am I on the right path and what upgrades would I benefit from for my application.

 

The stock transmission is barely adequate for stock HP levels. Add a programer to a transmission with 190k and you will blow it up in very short order. The biggest problem is the torque converter. Then you have the problems with the flywheel flexing. The valve body leaves a lot to be desired. The governor pressure solenoid is a weak spot. (Borg Werner makes a much beefier replacement.)

The best thing you can do since you are planning to haul a decent sized trailer is get that transmission rebuilt. Don't try to replace a part here and a part there. It will nickle and dime you and you still won't have a transmission that works good. To replace that transmission with exactly what is in there is usually around $3500. A "decent" upgraded transmission will run about $5,000-$7,000 installed.

I rebuilt my transmission myself almost a year ago. I pull a 6-8k trailer on a nearly daily basis and was having many of the issues you are. I decided to rebuild it on "my terms" and not when the truck decided to leave me stranded somewhere. When it was hooked up to a computer, you could see that there was a lot of internal "leakage" happening. Parts alone were about $3500. I have access to diesel shop that a really good friend owns and he gave me a hand. So far, everything has been working very well.

Below is a list of what was replaced. Other than the seal kit and pressure sensor, all parts are an upgrade from stock:

Torque converter (with a lower stall stator)
Flywheel
Billet input shaft
All new clutches and steels
Both bands were replaced
New band strut and anchor
Both servos were upgraded
New accumulator piston
All new seals/orings
Transgo shift kit (rework the existing valve body)
Another valve was upgraded in the valve body in addition to what the Transgo kit had
Borg Werner solenoid
new pressure sensor
Deeper transmission pan

 

Sounds like the classic 48re shuttle shift, an upgraded pressure sensor and transducer may resolve some of the shifting issues. As a minimum, it is usually reccomended to upgraded the torque converter and valve body if you plan on adding any power and save up for a rebuild. As long as you take it easy the truck should last you a while and easily haul 9k.

 

190k, rebuild it. Don't know if it's stock or been rebuilt before, but even half that and it's likely creeping up on 100k.


Programmer, nothing but the best, EFILive hands down. Period.

 

Ok well here's what I've come up with. Im taking it to my local dodge garage to have the sunroof glass replaced. While it is there I'm gonna have then check out the tranny. Whether that means a diagnostics test, test drive, pull off the pan and make a visual inspection. After I hear what they have to say ill be better informed on what my issue is. Does it make sense that the more I drive it the better it gets? Drove all day today and only noticed the hard shift once. It was shifting hard everytime when I first brought it home.

 

Granted mine's a bit older, but my rebuild ran less than $1000.
Billet torque converter, upgraded clutches, a drum that was starting to wear (which leads to leakage past the lip seal), shift kit, and some misc. other minor items. I'm not planning on hitting more than 400hp to the tires, as I'm not going to touch my turbo for the foreseeable future, so I didn't feel it warranted billet shafts or the like. Steels were all fine, no need to replace them. I rebuilt it at work with a coworker who is a 30+ year Chrysler trans guy.

 

http://doghousediesel.com/id18.html


This is a pretty good graph of what PARTS ALONE will cost for a given HP amount.

 

Ballpark, your mileage may vary kind of graph.

6.7 cummins + tuner + turbo back exhaust and EGR delete + lift pump will get you knocking on 500 hp at the tires, the 68rfe is perfectly fine at that level for most drivers who aren't beating the hell out of their truck.

5.9 common rail + tuner + lift pump gets you in about the same power range, but the auto does need attention, so 2 different 2007 model year trucks could be looking at two very different ballpark figures for a reliable 450/500hp daily driver setup.