i have been running my truck on level 2 for awhile now. The truck falls off and i am asumming that it is de-fueling. is anybody running their truck on level 2 with defueling off? or should i step up to level 3? not trying to hurt my tranny either.

I'm interested to see what people say because I know exactly what you are talking about. I've always kinda figured it was the de-fueling and figured something I would have to live with until the transmission is done.

Do you have the latest software update? I say that because my duramax used to do the samething until recently when I updated the software. It seems to have gotten much better.

my ppe seemed to do the same until i stepped up to the hot +2 e.t. i don't know if it was just me or the tuner but i thought the bigger tuner ran alot better and smoother even on the lower tunes. with the larger tuner you can turn off the de-fueling. i was also suggest updating it when ever new up dates come out.

i can turn defueling off on level 2. just not sure if it will hurt my stock trans, anyone run level 3 without any trans problems?

level 2 is fine..don't go over 100hp on stock tranny. you are right at the limit. defueling actually helps your trans and saves fuel. it's not as noticeable if you accelerate gradually.

i can turn defueling off on level 2. just not sure if it will hurt my stock trans, anyone run level 3 without any trans problems?

you can turn it off when you program it but i won't actually turn it off. i had a standard ppe and tried it with no luck. then i got the hot +et and when you turn it off you can really tell the difference.

We run ours on level 3 unless towing large loads and then we goto 2. Never used 4 or 5 since its a stock tranny.

I would try the trans relearn, and check and see if you have the current version 2.49. I ran lvl 3 for 25k , when I tow I drop it doen to lvl 2.
Lvl 4 and 5 are fun but trans life is limited.

You might be have FPRV trouble-- Here is a test to check--

On the drivers side fuel rail near the firewall there is a horse shoe shaped 1/4" hose close to the glow plug bracket. Disconnect the hose where it comes out of the fuel rail. Then hook up long hose and plug the "U" shaped hose.

Run the hose to somewhere that a bottle can be mounted. If your hose is long enough, you can mount it between the coolant tank, and airbox. Anywhere you can have the bottle standing in a upright position.

Now drive the truck hard, with some wide open throttle runs.

After you do this, check the bottle. If its empty, your FPRV is not bleeding off fuel and you don't need to shim the valve.

If it has more than a little fuel, that means that your fuel rail relief valve is leaking and you will then need to either shim the valve, or install a race valve.

i have version 2.49 loaded on it, i reset trans when i tuned it. i have been driving on level 2 and going back to stock when towing decent loads because i dont have an egt gauge. i will try the fprv test this weekend, its good to know people have been running level 3 with no ill effects on stock trannys.

You might be have FPRV trouble-- Here is a test to check--

On the drivers side fuel rail near the firewall there is a horse shoe shaped 1/4" hose close to the glow plug bracket. Disconnect the hose where it comes out of the fuel rail. Then hook up long hose and plug the "U" shaped hose.

Run the hose to somewhere that a bottle can be mounted. If your hose is long enough, you can mount it between the coolant tank, and airbox. Anywhere you can have the bottle standing in a upright position.

Now drive the truck hard, with some wide open throttle runs.

After you do this, check the bottle. If its empty, your FPRV is not bleeding off fuel and you don't need to shim the valve.

If it has more than a little fuel, that means that your fuel rail relief valve is leaking and you will then need to either shim the valve, or install a race valve.

Is there any ill side effects if the valve is shimmed, but was not necessary? I bought the shim kit a while back from ppe but haven't installed it yet. I was under the understanding when you start tuning the trucks to a point where the lift pump is needed that a shim kit was always a good idea to install.

The LLY FPRV has a known weak relief spring- There is no real problem, unless you jack it up to where it will not bleed any fuel off. I think that is hard on the CP3 and injectors.

I did not test mine, but I did add one washer under the spring. Of course I drive like an old man-- Sh*t, I guess I am. I will send you info on how I did the shim-- Jerry