try replacing the maf.your right when the maf is unplugged it shifts like **** hard.ive never heard of a maf goin bad to cause this but its worth a shot.

 

Already checked. MAF is fine.

I've posted this on LS1Tech and people seem to think it is the tune. I have a tuner checking the Diablo tune once I get back into town Friday. If it's confirmed the tune is ******* it up, Diablo is gonna have a hard time like they gave me.

 

well I dont think you will see anything out of the ordenary in the tune. For your sake I hope you do, but I doubt it. I would agree with everyone else, it sounds like it is going into limp mode. The ONLY other thing I could think that would make a trans shift hard after x amount of time and have nothing to do with trans temp, (right?) would be the adaptive tables. Which depending on the tuner your friend is going to use to read the tune, you wont even seen...

Have you used the Diablo while driving to check DTC?

It does it no matter how hot the trans is right? AS SO as you key off and key back on, it will shift right far a few minutes, right?

If so, then Something in the tune is causing it to go into limp, or the adaptive tables are WAY WAY out. and I doubt the adative tabbles could pull that off... Call Diablo back, talk to some-one else...

 

Diablo posted in my thread on LS1Tech and verified their older revision tunes caused this issue. They have no idea why their phone support fought me on this and refused to help. They're gonna fix the tune for me.

 

sweet!!

 

Yeah, I'm quite pleased. Thanks to everyone in this thread for your help

 

I'm sure if you had posted on Diablo forum on there web site you would got help also.
I had Diablo for 1.5yr before started mod truck with cam and turbo. I had them send me update tune for adding shift kit to my truck and when I added headers. Try post on Diablo forum next time to get help. There are allot guy that know there product well.

 

I don't think it matters whether I posted or called, I was still looking for a resolution and still got less than desirable customer service.

It's being taken care of.

 

On the 99 and early 00 this is a common problem with the tunes for our trucks. I had the same problem with mine and I got Diablo to write me a custom tune to prevent this from happening. If you go to their website and do a search on the forums, you will see that this happens quite alot. The only way to fix it is to get a custom tune from them.

 

Here is a link to the thread I started there.http://diablosport.com/index.php?nam...ighlight=u7198