Towing Performance with '03 ETC

[LEerkes]

Here's the set-up:



3500, SRW, ETC, 47RE, 3. 73's, 12,000 miles, towing a 6000# travel trailer.



Perhaps I overestimated the pulling power of the SO cummins? My main complaint is towing on the interstate. I was not able to maintain 65mph on a "normal" stretch of interstate. Granted this is NW Washington and there is no flat section of I-5 around here but no big long truck killers either.



In a nutshell, not enough ooommmph (technical term ) with the OD on. Even a slight uphill incline will cause a fairly rapid drop in speed. And, too large a change in output ratio from OD to 3rd to turn off the OD at highway speeds - doesn't seem right to run the thing at red line down the freeway.



Questions:



1. ) Is this normal for the standard output cummins? I thought the SO could handle 6000#'s, was I wrong?



2. ) What level of RPM's should I shoot for for sustained periods. 3000 seems a bit on the high side, I'll get pulled over for impeding traffic at 2000 with the OD off.



3. ) This truck is stock, no upgrades, not even any flashes. Can it be "fixed" or should I just dump it and buy the HO.



If it helps, I run at about 2/3 pedal and drop out of OD at about 50 and then mainain 2500 RPM's. Problem is I can't use OD unless the terrain is flat or downhill.



I believe that I am seeing TC lockup (based on the tach). And, I've had precious little time towing with it on the freeway (just a few miles), only owned it for a week, so a little practice may help a bit. I'll go take a look at the filter indicator tonight - I seem to recall quite a bit of yellow in that little glass bubble.



Any input would be greatly appreciated!!

 

[KLockliear]

1. While I don't drive in your area, I would think it should be able to maintain that, unless the trailer is tall (read as big sail). A box like our TTPM would likely fix that problem for you.



2. Try to stay under 2700rpm... that's where the pilot injection turns off and the EGT's climb rather quickly.



3. Plenty of upgrades available. I'd start with gauges and a box as mentioned above.

 

[rashwor]

My thoughts.

Yours sounds about right to me. Dump it or Bomb it. If you want to fly while loaded, bombing may be the answer, but it is a long expensive road. transmission will need to be upgraded to handle the power, then add power (box) as needed and pocketbook allows.



You could always dump it for a 04. 5 with a 6 speed manual. Then you say, "what 6000# behind me?"

 

[LEerkes]

Keith,



I have thousands of miles of towing experience and should have thought to include that in my original post. Yup, I do have plenty of sail area. The TT is a Trail-Bay 24BHDS, a Trail-Bay is one o'them 4x4 RV's, floor level is over the tires. Nothing really excessive though, my '79 F*** with a smoggy motor in it towed it fine down the freeway.

 

[Bertram65]

I have only towed with mine once and it was a disapointment. It was about 4500#s, it was a boat which is fairly aerodynamic but I could definetly tell it was there. The truck was pretty new so hopefully when I tow again it will be better.

 

[KRozeboom]

Check TSB 18-027-03 lack of power in OD and TSB 18-015-03 (will not shift out of 3rd).



I had these done on my SO and it seemed to help.

Ken

 

[LEerkes]

Thanks Ken,



I've had no flashes yet and those are on the list!

 

[Firewalker]

I just got bothe tsb's done that KRozeboom posted above and instantly i could tell a diffrence... I hopefull will be towing the camper next month and then we will see. .

Now on the other side get an edge box on setting three that is what i did and with the box and 9000 pounds i had no problem hitting 100mph... !!!!





Look for my other post, there are two flashes required for the tsb 18-027-03 one flash for the ECM and one flash for the PCM. .



The dealer had to look hard to find both !!!



Now as a test before bringing the truck in for the flash to the ECM.

unhook the batteries and urn the yey on and try to start...

This should leave a code... .



This would be one way of telling theat they reprogramed the ECM cust the program will wipe out all codes.

 

[LEerkes]

One more question to add:



Assuming I BOMB it and go with moderate changes starting with the 47RE and then a box. Will one of you guys with some experience throw out a number for me? How many pennies can I plan on spending? Are we talking $3,000 or $10,000?

 

[Archive]

My 04 pulls my toyhauler aprox 9000lbs fully loaded. GCWR of aprox. 17000lbs on the flats no problem. 48re stays in od the whole time doing 55 to 60 mph. If any of you are familiar with San Diego,going to Ramona on I67 the grade is somewhat steep. It holds 40mph in 2nd gear wot at aprox 2600 rpm. Egt temps pre turbo are 1150. 4:10 gears afe intake and banks 4 inch ex. Considering its a ca so Im very pleased!

 

[DPelletier]

LEerkes,

I have to concur that your experience sounds normal to me. My last truck was a 2001. 5 ETC with 47RE and 3. 55's. My trailer was about 6500 lbs (24' Kit Companion 23JT).

Bad news is that your trucks performance is likely normal - i. e. nothing wrong with it. You can try the reflashes, but don't hold your breath for drastic improvements.

Good news is that running your truck at sustained (relatively) high RPM's shouldn't do it any serious harm. I personally wouldn't bat an eye at running at 2500 - 2700 rpm all day long. I think my '01 had less issues with high EGT associated with higher RPM that the CP3 equiped trucks do, but I ran mine at 2800 - 2900 for over an hour straight all the time. Cummins R&D is alot harder on these things than we can ever be. Hey, Keith, why do the new trucks, '03 and up, seem more succeptable to rpm induced EGT's?

If you want more power, its easy enough to get. What you need to keep in mind is that anything more than a very light bomb (maybe EZ only), will require gauges, transmission upgrades, etc. etc. and your warranty is history.

I decided to get the HO, 6 speed instead and I'm very happy. The extra power is nice (70 hp, 95 ft lbs), but I think the transmission is a bigger difference. Two extra gears to keep the rpm's in the right range and the OD isn't as tall a ratio.



Anyway, if you decide to modify, Keith is a good guy for advice.



Good Luck,

Dave

 

[KLockliear]

If you are thinking of trying to go any further than the box, you should really consider a newer truck (perhaps an HO) with the 48RE. That 47RE will take the box and that's it. The 48RE will take up to 400rwhp.

 

[Got HO?]

12k miles

Have you replaced your fuel filter yet. Mine was very restricted after 9k miles & power & mileage perked up after the first replacement filter. Could be that Mexican diesel that fouled it up when new. The second filter (replaced at 20k miles) looked much cleaner. I replace mine every 10k miles now.

 

[KLockliear]

Originally posted by DPelletier

Hey, Keith, why do the new trucks, '03 and up, seem more succeptable to rpm induced EGT's?

Dave

Because the head flow sucks.

 

[RLighthall]

Erk,

Sounds like that's the norm for the SO. Pulling a 5500# load and a few hundred more in the bed, mine would do fine on the highway, but once I came to big hills it fell flat on its face. With the OD locked out I could only do 41 mph up the hill. Couldn't do a darn thing to make the TC unlock (to let me run higher rpm's) short of manually pulling it into 2nd, which just won't cut it on a 65 mph freeway. This made the engine lug at too low of rpm's to be healthy for the engine. Soooo, I'm trading it in on a 600 with the 48RE. I went with the 410 this time since most of my towing will be in the hills, and my daily drive is 60 someodd miles highway and another 60 someodd twisty back roads. In the pulling power dept. I'm going from one extreme to the other . The new ride shipped on the 7th of January, but since I'm back east it has to come via boat and DC says the boat both left Veracruz Mexico and arrived at the Port of Baltimore last Friday

 

[DPelletier]

Keith,

Thanks for the reply. So the 2nd gen heads flow better, I take it?

Wonder why they made the change then? I am starting to think a person would be better off with an '02 ETH DEE. Dana axles, HX-35 and now a better head.



Dave

 

[djbobo]

I had the 03' SO w/the 47re & it would not pull any hill in OD. I was faced with the same choices that you are. I had all the re-flashes performed & noticed no difference. My bone stock 98' 190hp with a 47re would out pull it in OD hands down. This led me to believe that this so called 250hp truck was probly programed to defuel once it hit overdrive to save the trannie during their warranty period. The SO's with the 5 speed didn't seem to have the loss of power in OD

Again my choices were;

-Upgrade trans. & bomb $ 3500-&4000 & loose warranties

-Trade

I traded & only lost 5 grand going to a 04'.

With the rebates & better financing my payment only went up $40 per month. Laramie to Laramie but did change up to dual rear wheels.

Now I'm happy with this lower output (555 ft lbs) engine. No more auto's for me - From now on I'll always wonder if those programing boys at DC did, or still do, Lower the hp levels in OD to help their warranty issues on the autos. You must agree that there seems to be an in-ordinate power loss in OD. Like I said - My 98' pulls like no tomorrow in OD & I expected the 03 to be the same - if not better.



good luck



dj

 

[David Muench]

My 03 SO with the 47RE had problems towing too in OD. The root cause for me is 3. 73 gears, automatic transmission, and 315 BFG's = rpms are too low at sane towing speeds in OD.



I am still kicking myself for not getting the 4. 10's. But I didn't think I'd upgrade the tires. I may regear, but for now at least the Edge EZ is enough of a bandaid. The reflashes mentioned above helped a lot too. Fortunately I don't tow often and don't tow heavy at the moment. I will in a few years though, so my next truck will probably be back to a 6 speed.

 

[KLockliear]

Originally posted by DPelletier

Keith,

Thanks for the reply. So the 2nd gen heads flow better, I take it?

Wonder why they made the change then? I am starting to think a person would be better off with an '02 ETH DEE. Dana axles, HX-35 and now a better head.



Dave

Why do they always change things... emissions and the darn CARB board! The 12v is actually the best.

 

[Agades]

12v's are cool



I wish I had one