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Posted

So I finally gave up on waiting for a fix for the 8 speed and its many mis-behaviors and had my truck tuned by a local custom tuner that has been working with LS/LT motors and transmission tuning for many years. He plugged in his laptop and rode with me for over two hours. The truck is a new animal. Great at shifting and the engine acts like the beast it should be.

 

My truck is a 2015, 6.2L 8 Speed, 23,000 miles. It has always had the low speed clunk and recently developed the shudder, especially in 8th at steady state highway speeds.

 

Here is some of what was done.

AFM shut off, Torque Management shut off, Variable cam timing adjusted to performance lift, 1st gear set to hold until 11 mph, higher shift pressure for next few gears, torque converter set to 0% slip, raised speeds for converter lockup especially in 8th. Other parameters were adjusted, but these were the main ones.

 

Some of what was learned.

The TC was slipping too much when trying to lock at light load (half in half out) causing the shudder. It was also trying to lock at too low of a speed/RPM almost lugging the engine (again most pronounced in 8th). No more shudder in any gear. It does take a decent speed (over 60-65 to lock up in 8th, but once locked it will stay locked below 60 unless I kick it in the pants or the load increases). As most of you experience, 1st gear was trying to get to third as quickly as possible. Now I can move through parking lots without trying to throw a U joint. There were more learnings but these 2 are the big ones.

 

I will probably lose a bit of MPG in town driving (I am fine with that) but the 60 mile trip home at freeway speeds netted 20.1 MPG ... not enough loss to consider if any. Performance is incredible. I floored it from a stop a couple days later, and had to back off to preserve the tires as it started roasting them. Shifting at full throttle was impeccable. Longevity (as long as I dont drive it live a sports car) theoretically will be better than it was with all the clunks and shudders. I am thrilled with the results.

 

If any of you live near Van Buren Arkansas, and are interested I will pass on the contact info.

  • Like 1
Posted
1 hour ago, quicksilver64 said:

So I finally gave up on waiting for a fix for the 8 speed and its many mis-behaviors and had my truck tuned by a local custom tuner that has been working with LS/LT motors and transmission tuning for many years. He plugged in his laptop and rode with me for over two hours. The truck is a new animal. Great at shifting and the engine acts like the beast it should be.

 

My truck is a 2015, 6.2L 8 Speed, 23,000 miles. It has always had the low speed clunk and recently developed the shudder, especially in 8th at steady state highway speeds.

 

Here is some of what was done.

AFM shut off, Torque Management shut off, Variable cam timing adjusted to performance lift, 1st gear set to hold until 11 mph, higher shift pressure for next few gears, torque converter set to 0% slip, raised speeds for converter lockup especially in 8th. Other parameters were adjusted, but these were the main ones.

 

Some of what was learned.

The TC was slipping too much when trying to lock at light load (half in half out) causing the shudder. It was also trying to lock at too low of a speed/RPM almost lugging the engine (again most pronounced in 8th). No more shudder in any gear. It does take a decent speed (over 60-65 to lock up in 8th, but once locked it will stay locked below 60 unless I kick it in the pants or the load increases). As most of you experience, 1st gear was trying to get to third as quickly as possible. Now I can move through parking lots without trying to throw a U joint. There were more learnings but these 2 are the big ones.

 

I will probably lose a bit of MPG in town driving (I am fine with that) but the 60 mile trip home at freeway speeds netted 20.1 MPG ... not enough loss to consider if any. Performance is incredible. I floored it from a stop a couple days later, and had to back off to preserve the tires as it started roasting them. Shifting at full throttle was impeccable. Longevity (as long as I dont drive it live a sports car) theoretically will be better than it was with all the clunks and shudders. I am thrilled with the results.

 

If any of you live near Van Buren Arkansas, and are interested I will pass on the contact info.

Man that sounds awesome. I feel like this 6.2 is capable of so much more. I also have an 8speed (2017 Sierra). I recently had the shudder issue fixed with a transmission flush at the dealer. But I would love for the truck to wake up a little and act like a 6.2 and not a 4.3. I’m up in Fayetteville,  so van buren is a short drive for me. 

Posted
2 hours ago, quicksilver64 said:

So I finally gave up on waiting for a fix for the 8 speed and its many mis-behaviors and had my truck tuned by a local custom tuner that has been working with LS/LT motors and transmission tuning for many years. He plugged in his laptop and rode with me for over two hours. The truck is a new animal. Great at shifting and the engine acts like the beast it should be.

 

My truck is a 2015, 6.2L 8 Speed, 23,000 miles. It has always had the low speed clunk and recently developed the shudder, especially in 8th at steady state highway speeds.

 

Here is some of what was done.

AFM shut off, Torque Management shut off, Variable cam timing adjusted to performance lift, 1st gear set to hold until 11 mph, higher shift pressure for next few gears, torque converter set to 0% slip, raised speeds for converter lockup especially in 8th. Other parameters were adjusted, but these were the main ones.

 

Some of what was learned.

The TC was slipping too much when trying to lock at light load (half in half out) causing the shudder. It was also trying to lock at too low of a speed/RPM almost lugging the engine (again most pronounced in 8th). No more shudder in any gear. It does take a decent speed (over 60-65 to lock up in 8th, but once locked it will stay locked below 60 unless I kick it in the pants or the load increases). As most of you experience, 1st gear was trying to get to third as quickly as possible. Now I can move through parking lots without trying to throw a U joint. There were more learnings but these 2 are the big ones.

 

I will probably lose a bit of MPG in town driving (I am fine with that) but the 60 mile trip home at freeway speeds netted 20.1 MPG ... not enough loss to consider if any. Performance is incredible. I floored it from a stop a couple days later, and had to back off to preserve the tires as it started roasting them. Shifting at full throttle was impeccable. Longevity (as long as I dont drive it live a sports car) theoretically will be better than it was with all the clunks and shudders. I am thrilled with the results.

 

If any of you live near Van Buren Arkansas, and are interested I will pass on the contact info.

I had my 6.2 tuned about a year ago.

 

The power never gets old. It never feels slow. I have no idea how a measely 420hp pushes 5500lbs so hard.

 

btw, you haven’t lived until you, put it in 4wd auto, turn off traction control(important), and launch it. Switch back to 2wd right after the launch (it just decouples the clutch diff, not bad for it at all)

Posted

Man I want a tune so bad. Gonna be years before the warranty is up though.

Sent from my SM-N910V using Tapatalk

Posted
1 minute ago, m3n00b said:

Man I want a tune so bad. Gonna be years before the warranty is up though.

Sent from my SM-N910V using Tapatalk
 

Search for evidence online that a truck’s drivetrain was denied a warranty claim because of just a tune. I couldn’t find any.

Posted
Search for evidence online that a truck’s drivetrain was denied a warranty claim because of just a tune. I couldn’t find any.

I know man. I just don't want to take the chance. Too much of a p*ssy I guess. Never bought any vehicle brand new before.

 

Sent from my SM-N910V using Tapatalk

 

 

 

  • Sad 1
Posted
25 minutes ago, m3n00b said:

I know man. I just don't want to take the chance. Too much of a p*ssy I guess. Never bought any vehicle brand new before.

 

Sent from my SM-N910V using Tapatalk

 

 

 

My first as well, im super duper cautious

 

I thought it if like this.

 

risk = worst case scenario = lost engine and trans, not covered under warranty, cost to replace $13k

chance of either one if them happening, realistic is likely 0.01%, but lets say the chance is 1%.

 

If you have a 1% chance of losing $13k, you can look at it as your tune is costing you an extra $130.

 

Just go with a reputable tuner and live a little. The truck is so much better. The risk, calculated accounting style, shows very little actual risk.

 

 

 

 

Posted
4 hours ago, truckguy82 said:

Search for evidence online that a truck’s drivetrain was denied a warranty claim because of just a tune. I couldn’t find any.

I've got a highly modified camaro and would take it in for warranty work no issues. 

  • 7 months later...
Posted
On 11/14/2017 at 2:57 PM, quicksilver64 said:

So I finally gave up on waiting for a fix for the 8 speed and its many mis-behaviors and had my truck tuned by a local custom tuner that has been working with LS/LT motors and transmission tuning for many years. He plugged in his laptop and rode with me for over two hours. The truck is a new animal. Great at shifting and the engine acts like the beast it should be.

 

My truck is a 2015, 6.2L 8 Speed, 23,000 miles. It has always had the low speed clunk and recently developed the shudder, especially in 8th at steady state highway speeds.

 

Here is some of what was done.

AFM shut off, Torque Management shut off, Variable cam timing adjusted to performance lift, 1st gear set to hold until 11 mph, higher shift pressure for next few gears, torque converter set to 0% slip, raised speeds for converter lockup especially in 8th. Other parameters were adjusted, but these were the main ones.

 

Some of what was learned.

The TC was slipping too much when trying to lock at light load (half in half out) causing the shudder. It was also trying to lock at too low of a speed/RPM almost lugging the engine (again most pronounced in 8th). No more shudder in any gear. It does take a decent speed (over 60-65 to lock up in 8th, but once locked it will stay locked below 60 unless I kick it in the pants or the load increases). As most of you experience, 1st gear was trying to get to third as quickly as possible. Now I can move through parking lots without trying to throw a U joint. There were more learnings but these 2 are the big ones.

 

I will probably lose a bit of MPG in town driving (I am fine with that) but the 60 mile trip home at freeway speeds netted 20.1 MPG ... not enough loss to consider if any. Performance is incredible. I floored it from a stop a couple days later, and had to back off to preserve the tires as it started roasting them. Shifting at full throttle was impeccable. Longevity (as long as I dont drive it live a sports car) theoretically will be better than it was with all the clunks and shudders. I am thrilled with the results.

 

If any of you live near Van Buren Arkansas, and are interested I will pass on the contact info.

Could you post the contact info please

Posted
On ‎2017‎-‎11‎-‎14 at 5:37 PM, m3n00b said:

Man I want a tune so bad. Gonna be years before the warranty is up though.

Sent from my SM-N910V using Tapatalk
 

With these K2's it seems like you can have all this crap tuned out and have a proper performing one, or you can not tune it, keep the warranty and fix broken parts, aids and driver nannies. 75% of the problems these trucks experience are around the AFM and trans tuning, so why not have it tuned by someone who knows what they are doing? Because let's be honest, you can't really screw up the tune, GM did a good enough job of that on their own. 

 

Now my 6.2L is acting up and vibrating in a pulsing pattern, I know full well it is going to be a AFM or torque converter issue. If it wasn't for the botched drivetrain tuning, these would have been the best trucks GM ever made. For now that trophy will remain with the 07-13's IMO. 

  • 2 years later...
Posted
On 11/14/2017 at 2:57 PM, quicksilver64 said:

So I finally gave up on waiting for a fix for the 8 speed and its many mis-behaviors and had my truck tuned by a local custom tuner that has been working with LS/LT motors and transmission tuning for many years. He plugged in his laptop and rode with me for over two hours. The truck is a new animal. Great at shifting and the engine acts like the beast it should be.

 

My truck is a 2015, 6.2L 8 Speed, 23,000 miles. It has always had the low speed clunk and recently developed the shudder, especially in 8th at steady state highway speeds.

 

Here is some of what was done.

AFM shut off, Torque Management shut off, Variable cam timing adjusted to performance lift, 1st gear set to hold until 11 mph, higher shift pressure for next few gears, torque converter set to 0% slip, raised speeds for converter lockup especially in 8th. Other parameters were adjusted, but these were the main ones.

 

Some of what was learned.

The TC was slipping too much when trying to lock at light load (half in half out) causing the shudder. It was also trying to lock at too low of a speed/RPM almost lugging the engine (again most pronounced in 8th). No more shudder in any gear. It does take a decent speed (over 60-65 to lock up in 8th, but once locked it will stay locked below 60 unless I kick it in the pants or the load increases). As most of you experience, 1st gear was trying to get to third as quickly as possible. Now I can move through parking lots without trying to throw a U joint. There were more learnings but these 2 are the big ones.

 

I will probably lose a bit of MPG in town driving (I am fine with that) but the 60 mile trip home at freeway speeds netted 20.1 MPG ... not enough loss to consider if any. Performance is incredible. I floored it from a stop a couple days later, and had to back off to preserve the tires as it started roasting them. Shifting at full throttle was impeccable. Longevity (as long as I dont drive it live a sports car) theoretically will be better than it was with all the clunks and shudders. I am thrilled with the results.

 

If any of you live near Van Buren Arkansas, and are interested I will pass on the contact info.

Hey man, I'm up in Bentonville and looking to get my truck (2018 6.2l, 8-speed) tuned by JP. I was wondering if you could provide an update on this, as to how the tune has performed over time... any issues or things worth noting? Thanks in advance!

  • Like 1
  • 2 months later...
Posted

I know you only have 23k or so miles on the truck but now would be a great time to change out all the transmission fluid. This way the transmission is fresh so to speak and any wear-in material from the poor performance before can get changed out.

  • 1 month later...

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