What tuner for 1999 Suburban (5.7 vortec)? Gear ratio change, need to calibrate speedo

[BowtieBrody]

The answer to this is yes, you can just buy a tuned PCM from them. There's a core charge in addition to the price of the tune ($50 or $60 IIRC) which you can choose to have refunded or not, depending on whether you want to keep your stock PCM or send it into them as a core. I kept mine so I'll always have another PCM to swap in if the tuned one needs to be sent in for adjustments, or I just feel like getting better gas mileage.



I was thinking a tune wouldn't help my truck much either really, especially considering the fact that my red truck has the 4.3L V6. It was a bigger improvement than anything else I've done to the truck by far. More noticeable than my full exhaust with shorty headers. Just made the truck way more fun to drive!

I understand if you really just want a programmer for the tire size and gear change, but I would not go messing around with the shift points or anything related to the 4L60E with a handheld programmer. 4L60Es are pretty weak. When I first got my Black Bear tune for the V6 truck I had them remove 100% of the factory torque management and firm up the shifts on my factory 4L60E, and about a week later it failed during a WOT 2-3 shift. Had it rebuilt and beefed up considerably (with parts that a user here, @rhino kindly helped me pick) and had Black Bear put all the TM back into the tune, but it still worries me. Even behind the V6. Be careful tweaking a 4L60E for sure.

A couple more questions pertaining to the BBP PCM and a transmission question,

Could I use a programmer to adjust tire-size/gear ratio with the tuned PCM or would that throw off the computer's operating tables?
And would a 4L80E with a Mag Hytec pan and a Trans-Go HD2 set to the mildest shift firmness be able to channel the full power of a 454 with TM disabled?

 

[df2x4]

A couple more questions pertaining to the BBP PCM and a transmission question,

Could I use a programmer to adjust tire-size/gear ratio with the tuned PCM or would that throw off the computer's operating tables?
And would a 4L80E with a Mag Hytec pan and a Trans-Go HD2 set to the mildest shift firmness be able to channel the full power of a 454 with TM disabled?

To answer the first question, I don't think so. Pretty sure you'd need to send it in for adjustment. Which they'll do for free, you just pay shipping.

The second, I'm really not qualified to say. Maybe @rhino or someone else well versed in tuning and/or transmissions could shed some light. My personal opinion though, as in what would I do if it were mine? I'd leave the TM alone. GM put it in there for a reason, and when I took it out things broke. On top of that, when I put it back to factory the trans still shifted almost exactly the same. Which is to say the HD2 kit will make a lot more difference than removing TM anyway. On top of THAT, I did before and after quarter mile runs in my slow ass V6 truck with the only variable being the TM in the tune, and it was actually consistently quicker by a couple tenths with the TM left factory and untouched. My theory is less traction loss on the 1-2 shift but who knows.

4L80Es are super strong. I'd do the HD2 and leave it alone. The Sloppy Mechanics Colorado just ran a 9.something quarter mile with a stock 4L80E and an HD2 kit. EDIT - And Matt has said he doesn't touch the TM in his tunes.

 

[Jorge6.5]

Had the hd2 kit in my past 4l80e, it rocked!

 

[Christian Steffen]

To answer the first question, I don't think so. Pretty sure you'd need to send it in for adjustment. Which they'll do for free, you just pay shipping.

The second, I'm really not qualified to say. Maybe @rhino or someone else well versed in tuning and/or transmissions could shed some light. My personal opinion though, as in what would I do if it were mine? I'd leave the TM alone. GM put it in there for a reason, and when I took it out things broke. On top of that, when I put it back to factory the trans still shifted almost exactly the same. Which is to say the HD2 kit will make a lot more difference than removing TM anyway. On top of THAT, I did before and after quarter mile runs in my slow ass V6 truck with the only variable being the TM in the tune, and it was actually consistently quicker by a couple tenths with the TM left factory and untouched. My theory is less traction loss on the 1-2 shift but who knows.

4L80Es are super strong. I'd do the HD2 and leave it alone. The Sloppy Mechanics Colorado just ran a 9.something quarter mile with a stock 4L80E and an HD2 kit. EDIT - And Matt has said he doesn't touch the TM in his tunes.

With a HD2 i think you'd be able to delete TM and be fine, as long as the shift pressures are left stock in the tune when the shift kit is installed. I've read that a 4L80e with a HD2 should handle 700hp (keep in mind that is likely in a car, not a 6500 lb pickup), so unless you really mod your 454 you'll be fine.

I've been running ~40k miles with TM deleted (Note: line pressure is raised, and shift time lowered in the tune) on my 489 and my transmission shows no signs of issues. I just change the fluid every 25k and make sure it stays cool.

 

[redfishsc]

I got my Flashpaq (used) off Ebay the other day. Reprogrammed the Sub, had to try a couple different tire sizes to match what my 2 GPS based speedometers would say. Got it pretty close, it's reading about 1mph higher than the GPS, so I'll leave it as it is.

I also figured I'd try changing the line pressure with the Flashpaq (transmission line pressure). I tried the 2 and 4psi increase, and i honestly don't feel a bit of improvement. Butt dyno indicates that it actually is a bit more sluggish at these, so I'm going to put the line pressure back to stock.

 

[Christian Steffen]

I got my Flashpaq (used) off Ebay the other day. Reprogrammed the Sub, had to try a couple different tire sizes to match what my 2 GPS based speedometers would say. Got it pretty close, it's reading about 1mph higher than the GPS, so I'll leave it as it is.

I also figured I'd try changing the line pressure with the Flashpaq (transmission line pressure). I tried the 2 and 4psi increase, and i honestly don't feel a bit of improvement. Butt dyno indicates that it actually is a bit more sluggish at these, so I'm going to put the line pressure back to stock.

2-4 psi isn't really much of a change.