Custom Tune Review!

[jdwood1111]

Hi All,

I wanted to post a review of a local tuner I just had a 2.5 hour road tune with this past Saturday (longish read an maybe not organized by I tried lol). This was my first time ever experiencing a tune of a car. I have done some minor performance mods here and there throughout the years but never took the leap to tuning. I have been hesitant to spend the money on the tune because a variety of personal/family reasons and concerns over the longevity of the vehicle since I have only had the car for under a year and do not drive it much as its a second vehicle but said screw it! I was going to pull the trigger on Black Bear but stumbled upon KP Tuning in Warminster, PA, 20 mins from my house and all I can say is Karl is awesome at what he does!!

Vehicle - Quick truck stats so you do not need to read my other threads, 2011 XL Denali bought last May with 92k miles and now has 96.6K miles. Completed a bunch of maintenance prior to the tune and the truck seems to run quite well with one exception, the transmission. When the temperature gets above 135-140 degrees, it gets clunky and would clunk/bang down from either 3-2 or 2-1. I took it to two transmissions places both of who test drove and said it was fine with the second one completing the fluid and filter and said the pan looked great. However, I noticed after the service the bang got a little harsher. No other shift problems anywhere else and figured lets see if the tune helps.

Goals - I did not really tell Karl much and he seemed to have a darn good base setting for these trucks. He does tons of LS motors and had a sweet camaro, CTV turbo and what appeared to be a twin turbo mustang in his shop next to his dyno. I really only wanted the AFM off and the transmission tuning done leaving whatever engine performance a bonus.

Process - Met with Karl around 10am and he was ready to go! Hooked up his laptop, used HPtuners to take inital readings, make a few changes, etc. He then hooked up the exhaust connector and said lets go. I started driving the truck and immediately noticed a significant difference in the truck. The transmission was no longer hunting to stay in the lowest gear as he turned off the TCC from 1-4 among other things. We drove around for a bit while he monitored things and then we pulled into a parking lot and had me turn off the truck and uploaded a few changes. This happened about 3-4 times. One of them was a WOT and WHOA was that different then before! He laughed and said pull in over here and had to turn the timing back down a little bit. One more WOT and he said perfect and man it makes a difference! Had made tons of changes to spark, timing, fuel, etc. that I have no idea but it works. The truck was so much more drivable and SMOOTH. The biggest improvement for me was when coasting at lower speed and then rolling back onto the throttle, I felt I had to go easy because the transmission was jerky. This is now gone!

THEN, as we were stopping at a light, the truck banged from 3-2 again and seemed harder than before. He then went into some tables for the 3-2, 2-1 and 3-1 shifts that I think said transmission oil temp (do not quote me on this as it may have been pressures but the numbers were in the 130-140's) and increased them by 10%. This made it worse. He then decreased them by 10% which made it a little better. He then decreased it by I think around 30-35% (after a couple more iterations) and it improved it a lot! It seemed to be slower going into the lower gears but it did not bang anymore. You can feel it but certainly does not bang. This appears to be an issue with mine that I do not attribute to him that I will have to keep an eye one as I drive it more. Still makes me concerned but this has little/nothing to do with Karl's adjustments (experienced it before) and had this not happened I would have been stoked with his tune regardless. Still not sure why it was only happening when the trans oil gets hot and not cold, valve body ball maybe, still need to research that I guess.

KP Tuning Review - Karl is an awesome cool dude! He has been doing this since 2009 and was going to go full time 2 years ago but kept his main job and this part time now. He has his own dyno and has done some REALLY nice vehicles! I would go to him in a second for another tune or any updates if required and would recommend him to anyone. I have nothing to compare him to but he was awesome none the less!

SHORT VERSION - 2011 XL Denali, 96.6k miles, custom road tune by KP Tuning is quite worth the money!! If you are on the fence, definitely have it done!

 

[SpineDock]

Stoked for you man!!
I am still newer to the forum but I’m sure the gurus will chime in to help with the bang/clunky tranny.
Did he also do the AFM delete?
What was the cost for the tune?

 

[jdwood1111]

Stoked for you man!!
I am still newer to the forum but I’m sure the gurus will chime in to help with the bang/clunky tranny.
Did he also do the AFM delete?
What was the cost for the tune?

Thanks! Yes he disabled AFM right away! Guess I forgot the price lol but it was $600. I think his normal dyno tune price is $700.

 

[OR VietVet]

I recently won a "traditional tune" at BBP. Was easy and trouble free. Love what they did and I personally, would not want to do more than I got. I do know my rig is in top notch condition at all times, so I had no worries there. Maybe @rockola1971 can chime in with the transmission concerns.

 

[rockola1971]

@jdwood1111 Im guessing when you say the tranny is "banging" that you are referring to a harsh shift up/down.

This vehicle has almost 100k on the clock and these trannys generally last 125k or so depending on alot of variables such as towing duty, snowplowing, climate that they are operated in and even amount of hills/mountains that are driven through often.

While the transmission might appear to be "OK".....Its not. Its getting close to the end of its life cycle before a rebuild is needed. Now is it impossible that this tranny will last to 200k with the driving that you do? Nope, not at all.

The stereotypical wear items in a tranny when a rebuild is needed involves the brains of the thing. The valve body. This thing controls everything that happens in a tranny either directly or indirectly.

As an example. 2nd gear (or 4th for that matter) will not happen without certain valves in the valve body operating correctly (no leak by, no seizing in bore), specific solenoid working correctly and ultimately the 2-4 band servo along with the band itself. Then of course there are clutches and mechanical gears involved too.

Assuming nobody got into PCM and made changes before. Everything points to valve body components worn and/or 2-4 servo worn. A defective valve body will eventually destroy the tranny. Same goes for a seizing 2-4 servo. It will burn the band up and overheat the sunshell.

If it were me at this point I would probably either plan for a complete rebuild or atleast install a rebuilt valve body (or have yours rebuilt) and while under the Yukon install a new 2-4 servo (corvette type), along with new shift solenoids. All of this can be done in your driveway/garage if need be too. Just be clean, very clean about it.

 

[swathdiver]

Yeah, I would look it over with a Tech-2 and probably replace the solenoids in the TECHM at minimum. @skpyle

 

[jdwood1111]

@jdwood1111 Im guessing when you say the tranny is "banging" that you are referring to a harsh shift up/down.

This vehicle has almost 100k on the clock and these trannys generally last 125k or so depending on alot of variables such as towing duty, snowplowing, climate that they are operated in and even amount of hills/mountains that are driven through often.

While the transmission might appear to be "OK".....Its not. Its getting close to the end of its life cycle before a rebuild is needed. Now is it impossible that this tranny will last to 200k with the driving that you do? Nope, not at all.

The stereotypical wear items in a tranny when a rebuild is needed involves the brains of the thing. The valve body. This thing controls everything that happens in a tranny either directly or indirectly.

As an example. 2nd gear (or 4th for that matter) will not happen without certain valves in the valve body operating correctly (no leak by, no seizing in bore), specific solenoid working correctly and ultimately the 2-4 band servo along with the band itself. Then of course there are clutches and mechanical gears involved too.

Assuming nobody got into PCM and made changes before. Everything points to valve body components worn and/or 2-4 servo worn. A defective valve body will eventually destroy the tranny. Same goes for a seizing 2-4 servo. It will burn the band up and overheat the sunshell.

If it were me at this point I would probably either plan for a complete rebuild or atleast install a rebuilt valve body (or have yours rebuilt) and while under the Yukon install a new 2-4 servo (corvette type), along with new shift solenoids. All of this can be done in your driveway/garage if need be too. Just be clean, very clean about it.

Yes I am referring to a harsh down shift from 3-2 mostly. Sometimes it’s harsh from 2-1 sometimes it’s not. However, it’s never harsh on up shifts at all. Only when it’s hot downshifts when coming to a stop.

Would the remanufactured valve body by Sonnax on rock auto be a good option? If I did that would the tuner need to readjust things?

Any videos or tutorials for the 2-4 servo? I thought the newer 6l80 did not have them. Are they easy to replace?

@swathdriver what all would the tech2 tell me that the tuner would not have been able to observe during the road test?

 

[rockola1971]

Yes I am referring to a harsh down shift from 3-2 mostly. Sometimes it’s harsh from 2-1 sometimes it’s not. However, it’s never harsh on up shifts at all. Only when it’s hot downshifts when coming to a stop.

Would the remanufactured valve body by Sonnax on rock auto be a good option? If I did that would the tuner need to readjust things?

Any videos or tutorials for the 2-4 servo? I thought the newer 6l80 did not have them. Are they easy to replace?

@swathdriver what all would the tech2 tell me that the tuner would not have been able to observe during the road test?

If you have the 6L80E then you have a different animal vs the 4l60E. A rebuilt unit from rockauto/Sonax will work great. Your tuner might have to redo the tables for the tranny but dont be surprised if its not needed.
You will likely find that the valve body TCM has bad pressure switches and likely have some valves that have worn into their bores in the valve body and are getting seized up. 6L80E has no servos.

What usually happens on the 6L80E is they crack around the bearing support in the 1-4 drum.
Try this video for some insight:

 

[OR VietVet]

Even the guys that tear these transmissions down all the time, lay the different parts they pull out, in an order. Work smart, not hard.

 

[rockola1971]

Even the guys that tear these transmissions down all the time, lay the different parts they pull out, in an order. Work smart, not hard.

Thats how I was taught many years ago....starting with the BW T-5 manual tranny. Lay everything out in order that you were taught and reverse once its time for reassembly.