How much extra power can one make without unwanted wear?

[LurkingLuke]

I read someone with a 6.2 who got a Black Bear tune, not much else. Maybe CAI, exhaust as well? Regardless, he wrote that he had to start replacing motor mounts frequently, as the was too much torque hitting the chassis.

I don't want to use a single stranger's story as my guide, so let me ask this: is this problem feasible on my Yukon 6.2? I want things to run better, not worse. Aiming for >300k miles before swapping in a turnkey factory motor.

 

[Marky Dissod]

You want Hummer motor mounts, not standard motor mounts, especially after a tune that removes torque management.

 

[Tonyrodz]

I'm sure he was mashing the go peddle much more then when it was stock. I can't blame him--so much more fun. I'm sure you won't have motor mount issues if you don't romp it at every stop sign and light.

 

[strutaeng]

From a tune only? Engine only or you talking overall vehicle? I doubt that's going to make much difference in the life of the engine. Afterall, how much more can you actually gain from only a tune? HP/TQ-wise? 20-30 HP maybe? IDK.

What would matter more are things like regular maintenance such as regular oil changes and driving styles. Lot's of highway miles vs mostly city driving miles idling in bumber-to-bumper traffic. Heavy towing? Lugging the engine (loading the engine below the powerband RPM) regularly? Driving like a madman doing donuts every night on the way to Starbucks?

"Power adders" like superchargers, turbocharger or nitrous is what will shorten the life of an engine as it puts much higher stress on everything on the engine. Maybe if you do a radical high lift cam swap also? If you are not doing any of that, I wouldn't worry about it.

 

[Doubeleive]

you could add a sail to it without any extra wear,
but otherwise ya the motor mounts are liquid filled and are a failure point eventually, the fix as already noted it to use the Hummer H2 solid mounts.
other failure points are the torque converter in the 6l80, the fix is to replace it with a billet converter before it begins to fail
otherwise you just have typical stuff that fails over time usually tied directly to the mileage driven.
there really isnt anything inherently wrong with the gmt900's otherwise than some sticky lifters that can happen from the dod and failure to maintain the vehicle with regular oil changes (some have associated it with dirty oil)

 

[Monz11]

I read someone with a 6.2 who got a Black Bear tune, not much else. Maybe CAI, exhaust as well? Regardless, he wrote that he had to start replacing motor mounts frequently, as the was too much torque hitting the chassis.

I don't want to use a single stranger's story as my guide, so let me ask this: is this problem feasible on my Yukon 6.2? I want things to run better, not worse. Aiming for >300k miles before swapping in a turnkey factory motor.

Check out Atomic Fab poly mounts, will help ride and never need repair https://atomicfabandperformance.com/product/07-14-gmt900-poly-motor-mounts/

 

[Marky Dissod]

Y'know, you could ... also ... um ... not stomp on the throttle like you're trying to ****** a hissing cockroach?
Roll into it, if y'know what I mean?

 

[LurkingLuke]

Y'know, you could ... also ... um ... not stomp on the throttle like you're trying to ****** a hissing cockroach?
Roll into it, if y'know what I mean?

Old Friend: Moments like this really make it look life your handle is "Marky DISSED"

 

[Marky Dissod]

My point was that the reason why that other guy needed new motor mounts was not because his tune removed the torque management.
It was because he stomped on the throttle like M. Bison stomping on another street fighter's head.
He could've left torque mngmnt in the tune, or, he could've rolled on the throttle.

The driver is always the most important mod.

And for the record, every new yorker has myrdyrrd hundreds of thousands of cockroaches.

 

[ThisIsLivin]

I did the complete AFM removal with bushed rockers my own tune CAI and Gibson exhaust and according to the internal torque sensor, I’m making 464hp and 507ftlbs. I hit the go pedal pretty hard and I have over 214,000 miles and no problems. FYI if you do the AFM delete you can reduce the TC slippage and get amazing mileage. My best segment average is 28.1mpg. I love it that with over size tires, I get rubber in second in a full size SUV.

 

[Rocket Man]

Replace the crappy-design fluid-filled motor mounts with solid rubber ones fron a Hummer H2 which are a solid RUBBER design like the previous generation or solid POLY from Atomic Fab (hard plastic design which is rougher at idle) and you can go ahead and install not only that tune and exhaust, but go ahead with the cam, roller rockers, long tube headers, and supercharger like I did on my 02 -which I did at 150k miles. It’s still going strong. Fun as hell to drive too. No extra wear except on everything. Thus the 16” Wilwood brakes.

 

[Scrappycrow]

FYI if you do the AFM delete you can reduce the TC slippage and get amazing mileage.

What is the interplay that's going on here?

I will be getting an HP Tuners MPVI3 soon and delve into adjusting things, but have to admit that learning everything is like drinking from a firehose, so I haven't run across this yet. Any suggestions on what to research WRT this?

 

[strutaeng]

What is the interplay that's going on here?

I will be getting an HP Tuners MPVI3 soon and delve into adjusting things, but have to admit that learning everything is like drinking from a firehose, so I haven't run across this yet. Any suggestions on what to research WRT this?

It's just some checkboxes or "disable" drop-down menus.

This source is A LOT more in-depth if you have time:

I own an '20 Express Van that has the L96/6L90e. Recently became aware HP Tuners now supports that model. Previously I have only done basic things like VATS delete, gear ratio change, etc on the Gen III engine vehicles. I will be purchasing the credits for our van hopefully this year and disabling the torque converter slippage settings. Luckily no DOD/AFM to worry about on that one.

 

[Scrappycrow]

Thanks, strutaeng! I definitely have the time to spend to do it right.

​

 

[Rocket Man]

Thanks, strutaeng! I definitely have the time to spend to do it right.

​

Make sure you know absolutely what you’re doing with HPT if you go that route. There’s plenty of people that have destroyed both transmissions as well as engines by tuning them. One bad mistake and it’s over, all it takes is a couple “small” changes in the tune.

 

[Scrappycrow]

Make sure you know absolutely what you’re doing with HPT if you go that route. There’s plenty of people that have destroyed both transmissions as well as engines by tuning them. One bad mistake and it’s over, all it takes is a couple “small” changes in the tune.

Understood. That's good advice.

I've got a good bit of experience with engine tuning, running from carbs/distributors, to Electromotive TECII, to Megasquirt, and I've got a Holley Stealth Terminator (HP ECU) sitting on the shelf for my '57 Chevy. I have no transmission ECU tuning experience, though.

 

[Marky Dissod]

FYI if you do the AFM delete you can reduce the TC slippage and get amazing mileage. My best segment average is 28.1MpG.

What is the interplay that's going on here?

1. Are you asking about reducing torque converter clutch slippage after deactivating V4 mode?
2. Or getting good MpGs despite deactivating V4 mode?

 

[Scrappycrow]

1. Are you asking about reducing torque converter clutch slippage after deactivating V4 mode?
2. Or getting good MpGs despite deactivating V4 mode?

I am asking why torque converter clutch slippage is relevant to AFM.

 

[Marky Dissod]

I am asking why torque converter clutch slippage is relevant to AFM.

I THINK it's something to do with the torque converter and/or its clutch staying locked during transitions from V8 to V4 mode and from V4 to V8 mode.

It's a great question. I hope someone lays down a good answer.

 

[mikez71]

Don't know if it's relevant, but..
stock setting, there is a target of 20 rpm slip for the TCC. 40 rpm if AFM is active.
People like to zero the slip apparently.