01 Yukon Denali Build Thread

[Rocket Man]

Yeah, likely right. I was looking at a windage tray and pan I have from the old 6.0L I put in my Camaro, not likely it came through there. Now that it's dropped temps, I really don't want to get under there and drop that pan though lol, especially with Michigan temps where they are now. I think I'll keep going as is, since I haven't heard it again, see how things go.
Or I'll find a REALLY steep hill to park it on and hope it rolls out the back of the tray

If something did fall down there, it’s not gonna hurt to leave it. It’s not going anywhere. I left that piece in mine for quite awhile but eventually it bugged me enough to drop the pan and retrieve it. The only time it could cause trouble is if the engine got turned upside down, in which case you’d have more than that bolt to worry about.

 

[drdave81]

Logged my drive and sent it off to Justin. Didn't get a reply I wanted, he noticed 1st to 2nd shift is slipping pretty good under load. I hadn't felt anything really noticeable before, but I can't say I'm terribly surprised with 208,000 on it and I'd assume original trans. Soooooo, I'm looking at Performabuilt and asking around locally to see if any shops are recommended.
I could also make it a winter project and build it myself. I haven't been inside a trans since college though, not sure I want to go that route. If I did, I'd likely earn my YouTube Certified Trans Tech badge though lol.

 

[Rocket Man]

If you go with Performabuilt you won’t be disappointed. I have their Level 3 in my blown and cammed 02 Denali. They rebuilt it twice for free, due completely to my fault. I did not know not to use RTV on the pan gasket and what happens is the servo passages at the pan rail get plugged up and they don’t release so the shifting is extremely hard. Both times after break in at 2000 miles, when their instructions said to change the filter and fluid, I used RTV on that gasket and both times shortly after that I destroyed the trans on a WOT 1-2 shift. The last time it twisted the output shaft like a pretzel and snapped it. It always shifted a bit hard due to my tune so I didn’t really think it was shifting that much harder. The second time it was way out of warranty but they not only covered it but they discovered the problem and let me know about the RTV. They’re stand-up dudes and Ryan is a smart mofo when it comes to these transmissions. They build some of their own parts and do some proprietary mods to fix known issues with these. The Level 3 is rated for 800 HP and I’m nowhere near that but with AWD on a heavy truck like these and then power adders on top, I have to say it’s performed great for the last 2 years after figuring out what my problem was.

 

[Sam Harris]

If you go with Performabuilt you won’t be disappointed. I have their Level 3 in my blown and cammed 02 Denali. They rebuilt it twice for free, due completely to my fault. I did not know not to use RTV on the pan gasket and what happens is the servo passages at the pan rail get plugged up and they don’t release so the shifting is extremely hard. Both times after break in at 2000 miles, when their instructions said to change the filter and fluid, I used RTV on that gasket and both times shortly after that I destroyed the trans on a WOT 1-2 shift. The last time it twisted the output shaft like a pretzel and snapped it. It always shifted a bit hard due to my tune so I didn’t really think it was shifting that much harder. The second time it was way out of warranty but they not only covered it but they discovered the problem and let me know about the RTV. They’re stand-up dudes and Ryan is a smart mofo when it comes to these transmissions. They build some of their own parts and do some proprietary mods to fix known issues with these. The Level 3 is rated for 800 HP and I’m nowhere near that but with AWD on a heavy truck like these and then power adders on top, I have to say it’s performed great for the last 2 years after figuring out what my problem was.

This guy.. glowing reviews from him are what led me to Performabuilt as well. I’ve only had mine since July, but have to say I’m extremely satisfied so far!

ETA: I opted for the level 3 as well. Not that I have a blower on mine, but hope to add some forced induction sometime in the future. Looking at the hard parts upgrades, and considering the weight of my rig, multiplied by the weight of my foot, compounded by my cam and heads upgrades, to the power of the open roads, directly proportional to the dopamine released when the pedal on the right is lowered… well, it was a no brainer.

 

[drdave81]

I found a pretty reputable guy near by that does a lot of performance builds on these transmissions. Been doing it a long time, typical gear head. I think I'll go with him, if for nothing else, he's 15 minutes from my house and sounds like it'll be about half as much as Performabuilt, give or take depending on what other upgrades I go with. His turn around time is about 3-4 days right now so pretty quick too. I did another log, per Justin, so we'll see what he comes back with, but the trans will probably happen sometime over winter, since I have a beater truck to keep the salt off this one. I'd like to keep it rust free, which is impossible in Michigan if you drive it in the winter.

 

[drdave81]

Haven't really done anything on this yet, trans will be coming out soon though. I've been tied up with other house projects, bathroom remodel. I haven't been in much of a rush since I'm not driving it a whole lot, even though we haven't had much snow in Michigan. I'm thinking it'll come out next month or so and get it to the shop to be rebuilt. I'll do the last two gaskets behind the trans while it's out. They are the only two left that haven't been done yet on the whole engine.

I've also started looking into swapping an NNBS intake. Initially it looked like it can't be done on the 00-02 DBW unless I got a pretty expensive LS2 throttle body, but then I came across @Buggdave build thread and how he was able to do it by repinning the connector and a little file work on the gear for the throttle blade. So a trip to a junkyard for an intake, some flex fuel injectors and a fuel rail to keep the return style fuel rail will be in my future, at some point.

I also have those 799 heads that I need to either get work done on or get rid of and get some new ported heads. Not sure if that will happen this year or not though. I'm still not happy about just how bad that one head was. Amazing how someone can be so careless about how they work on stuff.

 

[Geotrash]

Haven't really done anything on this yet, trans will be coming out soon though. I've been tied up with other house projects, bathroom remodel. I haven't been in much of a rush since I'm not driving it a whole lot, even though we haven't had much snow in Michigan. I'm thinking it'll come out next month or so and get it to the shop to be rebuilt. I'll do the last two gaskets behind the trans while it's out. They are the only two left that haven't been done yet on the whole engine.

I've also started looking into swapping an NNBS intake. Initially it looked like it can't be done on the 00-02 DBW unless I got a pretty expensive LS2 throttle body, but then I came across @Buggdave build thread and how he was able to do it by repinning the connector and a little file work on the gear for the throttle blade. So a trip to a junkyard for an intake, some flex fuel injectors and a fuel rail to keep the return style fuel rail will be in my future, at some point.

I also have those 799 heads that I need to either get work done on or get rid of and get some new ported heads. Not sure if that will happen this year or not though. I'm still not happy about just how bad that one head was. Amazing how someone can be so careless about how they work on stuff.

Helicoils are reasonably easy to do right. If those 799 heads are good except for a few bolt holes being stripped, you could do those yourself and they'd be as good as new. I stripped out one of the holes that holds the oil cooler lines on my 2012, and it's in a really tough spot to get to. Bought a low profile angle drill and was able to finagle it in there just enough to drill it, tap it, and get the helicoil set. Installed the lines and the repair held up to the full torque spec.

 

[drdave81]

Between a bathroom remodel and a ton of other stuff, this got pushed to the back burner for a while. I finally did get the trans rebuilt. I found a shop 10 minutes from my house who did it with all the upgraded internals; corvette servo, hardened sunshell, etc etc, and a trailblazer torque converter for $1250 (I did the R&I). Man what a difference a freshly rebuilt trans makes, compared to 200k miles lol. I have to get it data logged and sent back out to Blackbear, probably later today. Happy to finally be driving this again, well I was somewhat before, but knew I was on borrowed time with that trans so I never drove it far from home.

 

[Rocket Man]

Between a bathroom remodel and a ton of other stuff, this got pushed to the back burner for a while. I finally did get the trans rebuilt. I found a shop 10 minutes from my house who did it with all the upgraded internals; corvette servo, hardened sunshell, etc etc, and a trailblazer torque converter for $1250 (I did the R&I). Man what a difference a freshly rebuilt trans makes, compared to 200k miles lol. I have to get it data logged and sent back out to Blackbear, probably later today. Happy to finally be driving this again, well I was somewhat before, but knew I was on borrowed time with that trans so I never drove it far from home.

You’ll really be liking it after a tune. They will adjust things like torque control, shift points, firmness etc. and that new transmission will shift firm and fast and won’t be hunting for gears. You’ll be surprised once again, believe me. A good tune will make a big difference with the engine and transmission both.

 

[drdave81]

I got it tuned, flashed and have been driving it around for a little while now. It's so much better than before. I'm sure that's a mix of the tune and having a rebuilt trans, but man is it so much better. I need to get out with my Dragy to see how much of a difference it made. Then flash the 91 octane tune in and see how much of a difference that makes. Temps are different than before, so that may play a bit of a difference in it. Maybe I'll wait until spring to try and get as close to similar conditions as possible.

I keep looking at upgrading the audio in it. The old bose all still works, but I know it could be better. If I do, it'll be a complete removal of the original system, new amp, new speakers, etc. I haven't decided if I want to have a box sitting in the back or not. I have an old Tahoe sub box that I could throw a shallow mount sub it. It's always such a pain trying to decide which speakers to go with. You never know how they will sound in your vehicle with your type of music.