What does TSB 18-037-04 actually do?

[DCornelius]

I know what symptoms this TSB is supposed to correct, but what are the actual effects of the reprogramming, i. e. what factors are adjusted to gain the fuel mileage/kill the white smoke?



I guess it sounds like a dumb question, but many posts on the subject report better off the bottom acceleration or less turbo lag. Other posts report that there is less acceleration when the truck is floored. Some report smoother shifting.



I just wish DC or Cummins could just spell it out and say for instance, "TSB 18-037-04 alters fuel delivery resulting in a 5 hp decrease and a 15 ft lbs decrease in torque, which in turn, results in an increase in fuel mileage... . It also adjusts the shifting program to allow for smoother shifts under light loading... blah blah blah" I would just like to see something like that so folks don't have to speculate.



How bout you?



David

 

[klenger]

If they told you, they would have to kill you afterward. I know for a fact that my truck is easier to wash and the radio works better since I had the TSB done.



In any case, I am very pleased with the results. 20. 5 MPG average when running empty since the TSB, and no noticable difference in towing performance.

 

[scootergmc]

I'm sure they just defueled the engine. I noticed a little loss of power, but the mileage gains are up. The transmission shifts much better. So I don't tow too much, so I'm not going to complain at all. I like it. I would still love to see a before and after dyno...

 

[OCarney]

I pull trailers for a living out of Indiana. Before the reflash, I would get 9. 1 -10. 6 mpg pulling a trailer. After the flash mileage went up 1. 5 to 2 mpg pulling the same trailer over the same route. The overhead is now reading . 5 to 1 mpg over hand calc. , as opposed to 2-3 mpg under hand calc. before relash. I also noticed a power increase especially going up hill through Kentucky & Tennessee. My mileage increased when I hit 15k, and the reflash helped a little more. Every mpg counts. I talked with TX Gooseneck & he had his done last week with similar results as mine. These are my results, seems there are differing results. All mileage hand calculated.

 

[swexlin]

I think it affects different trucks differently, maybe because of the original code that was in your truck. Coming from PSD-land, there were MANY different stock computer codes that could be in trucks from the same model year ( I had an APX-1, for example. ) This is the only reason I can think of that so many of us are getting different results.



I don't know if that applies here. The major result of the TSB on my truck is better transmission shifting. Actual mileage gain is minimal; maybe 0. 5-1 mpg, if that, over the same driving conditions. Overhead computer is now reads 1. 2-1. 5 high, before it was about 0. 2 high. I have noticed NO loss of power, in either the top or bottom ends.

 

[rotts4u]

I am one of the statisticians where I work and have been keeping detailed info on mine before and after the TSB and after 4-5 tanks after I see no statistically significant results.



In fact my highest tank ever occured before the tsb.



The overhead however reads higher than before but I now find it OVERSTATES the mpg now.



Don

 

[FlyBoy007]

I was very concerned about the TSB screwing up my truck. I was getting 14 unloaded country with a bit of city with air on high, good power and smooth.



After the TSB I am up to 17 in the same conditions with smoother running and shifting and NO loss of power in fact it seems better but only from my seat. I am very pleased, I think they adjusted the 1st and 3rd fueling event as the truck sounds more like a diesel without the pinging at idle. Overall as Larry the cable guy says "get er done".

 

[DCornelius]

We'll I'm sure I'll get it done eventually. I just wish I knew exactly what they're fiddling with.

 

[Sarge]

I plan on putting mine back on the same dyno I had her on when she was new. I just need to get a day off during the week to get it done. I will post the before and after dyno when I get them. Sarge

 

[Buddy's Ram]

I just had the TSB done today. Engine is quieter and the transmission shifts smoother.

Haven't driven far enough to check the mileage yet. I have a dyno run from before, So the next chance I get I will do an after run. Will post the results then. Seat of the pants feels no different.

 

[Hokey]

Had mine done this morning looking good but need some time to tell how much difference.

 

[CBrittan]

Mine was done on Friday and I am impressed! Before the flash over 6000 miles I had never seen mpg over 14. 2. For the first time now I see over 16. The engine is quieter, and runs smoother. I cannot detect any loss of power. As far as I am concerned, this re-flash is a 'must have'.

 

[JimP]

Tsb

I had the flash, and I think it made alot of improvements. One I really like is the second gear lock-up feature. When towing a heavy load up hill it will shift to torque conve rter lock-up in second gear,or you can select not to lug in third. Before the flash I didn't have that feature.



Jimp: Oo. Oo.

 

[Buddy's Ram]

It has only been a week since I had the reflash done, only burned 1/2 tank since then. you seem to be able to feather the throttle on the lower end more now, not as jerky. When the turbo kicks in though in comes on hard; I was crossing a multilane hiway turning on to the interstate in busy traffic. I got on it when the opening appeared and the rear tires broke loose :--) I hadn't been able to do that before!

 

[KD7GYJ]

I had it done but the truck is still burning the first tank of fuel. One thing for sure, the algorithm is different for calculating the fuel mileage. It is changing more frequently as I drive. I have about a 1/2 tank and the odometer reads about 300 miles. I've seen that before, the second half always drops off like a rock on a cliff.



The white smoke on start up is still there, in fact there is more white smoke at startup than before, but the engine doesn't have the flat spot and doesn't roar at 2200 rpm to red line. So I'm still debating this TSB.