I towed a heavy load yesterday for the first time with my 2003 SO and I'm pretty disappointed. I'm not sure this truck has much more power if any than my old 454 FI Chevy Dually. Course to the Chevy's credit it runs a lot more rear gear (no OD) and most of my towing yesterday was in OD in the Dodge. I was pulling I'm guessing about 9000lbs in an enclosed up and down the Kansas Flint Hills on I70, 60mph was about the best she would do without dropping out of overdrive on the bigger hills. It flat had to work hard even at that.

The only things I've done to the truck so far is pull the silencer ring, put a smooth intake tube and Amsoil Nano filter on it, everything else is stock. I know either the stock air box or that Amsoil Nano is restricting the air flow some, at WFO it pulls the air minder down to 35% on a brand new filter.

I'm just looking for the best towing power and mileage I can get from the truck and it's current performance ain't going to cut it. What would you guys sugguest doing first to get some power out of this thing? Exhaust next?

 

I thought towing in OD was taboo? I figured that is why there is a switch to turn it off.

 

I did on some of the bigger hills just to get up them, but didn't realize there was a problem with these tranny's pulling in OD? I know on the old chevy's with the 700r4's it was a problem. I think this truck has the 47re in it but not certain of that.

 

You can tow in OD with the new trucks no problem. Otherwise your top speed would be really slow while towing!

Try keeping the RPM's above 2,000 while pulling hills. If you were doing 60mph that probably wasn't enough speed to put your RPM's in the 2k range. Mine will also lose speed if I try to pull a hill with the RPM's under 2k. For some reason that seems to be the magic number (for power and fuel economy too!).

If you still need more power while towing you can try a Smarty or Quad XZT, but then your tranny won't like you very much.

 

I know the disapointment with the SO. I put an edge EZ on my 04 SO and it really made a big difference. I always ran it on level 3 and it would pull a 13,000 5th wheel just fine.

 

I would recommend the Quadzilla xzt. It should give you enough more power to hold that overdrive gear up the hills. You should be ok with the stock tranny with it too.

 

Would exhaust make enough difference that it would tow better? I've either gotta fix this thing up to pull the weight or get a different truck, I don't want to lope along at 60-65 on the interstate when pulling.

 

Just about anything will help you out with that SO engine. They are only 250 hp, not enough really to do anything. Any box, or programmer will give you significant gains. BUT, if you go too crazy you will have to watch your tranny, doing an upgrade there would be highly recommened. The good thing here is that even though you are starting out with a real low HP, any upgrade you do gets you to the same power as a HO

Kevin

 

With a 47re you should not tow hills in OD...period.... I ventilated my airbox put on a FASS and TST and towed for 100k with a 48re before I tore my flexplate apart and roached the tranny requiring a full rebuild and TC. If you update the TC to a triple disc, mod the valve body, and get a better flexplate you will be able to handle some power mods. Adding a box or programmer to what you have will only make your repair bills bigger. I'm sure you were getting a little better mileage with the SO versus the 454. Do the tranny first!!! ks

 

Appears the first thing to work on is the tranny. Are the 47re's worthwhile to buildup? I'm not even sure if I have a 47 or 48, are there any distinguishing features? When you're talking about valve body mod's do you mean like a shift kit or does it take an aftermarket valve body?

 

If you have a so engine you have a 48re. There should be an option list in the glove box that will tell you what you have. Im not sure if you can upgrade to a 48re, from a 47, although I dont see why not.

As for the mods, talk to a reputable high performance tranny builder (gorend, dtt etc) they will give you the straight goods on what you should do. Trannys for diesel trucks require different mods than for a gas engine due to the increased torque.

Kevin

 

I'm no stranger to tearing up transmissions lol, I've burnt the TH400 in my Nova up more times than I can count. One thing I've learned from all that is there are builders out there and there is "the" builder that most of the others copy. So who's the "man" on the diesel stuff?

 

Early 2003 S0's had the 47re aka AKRAM. Later builds 48re. A 47re can be made into a 48re...but it costs a little more.

There are several good companies and many shops that deal exclusively with one of the big companies. Depends where you live. If I lived in Colorado an area...ATS. Florida ....Suncoast, Michigan and area....HTS. East Coast or Texas ...DTT. Idaho...Goerend. These are just general areas. back to work. ks

 

i just got gone towing my mud truck and 2 4wheelers and the weight was close to 8k and i pulled it fine at 80 with the predator on tow and the puck on 50 and had plenty of getup at that speed to