Darkanion, Talk To Me About Your Predator...

Bish · December 28, 2007

Been thinking while Zaino-ing my truck....I've got S rated tires and I think I want to bump the speed limiter. Not ready for a custom tune until I put some miles on it but I may want to bump the timing a bit along with the limiter. I'm already supposed to run premium so I'm also curious how much you think you gained. I'm guessing you did the intake, exhaust, and tune around the same time but I'm curious how much is left on the table in the engine.

Long term I'm thinking I might go for dyno tuning session. There's a awd dyno not too far from me and I might go that route instead of mail order. Like I said though, I want to get a couple thousand miles to get broken in. Unfortunately, that will only take me about 6 or 7 weeks

Let me know as much as you feel like typing..Thanks.

Oh yeah, one more thing. Six speed seems confused at times. Downshifting too low when I lean into the throttle. I'm hoping it just needs to learn some as I'm only at 200 miles. I'm hoping when I punch it, it doesn't slam into first and start bumping the rev limiter

Darkanion · December 28, 2007

Wow, I think that's the first time I've been called by name in a topic! That was different! Kind of reminded of being called to the principals office, back in school....... not that I was ever in any trouble or anything..

I've got S rated tires

Same here. I ordered some tires today, though, for the new (to me) wheels. I decided to get H-rated, "just in case." I don't run the truck real fast very often, but why chance an S-rated tire coming apart at 120+?

and I think I want to bump the speed limiter. Not ready for a custom tune until I put some miles on it but I may want to bump the timing a bit along with the limiter. I'm already supposed to run premium so I'm also curious how much you think you gained. I'm guessing you did the intake, exhaust, and tune around the same time but I'm curious how much is left on the table in the engine.

I've thought about a custom tune and I may go that route, at some point. It seems like people have good and bad things to say about all the options, whether it be the hand-helds or the various custom tunes.

Most people agree that a dyno is probably the best way to go, to get the most out of 'your' truck. Having not driven a dyno'd Sierra Denali, I don't know what "else" can be gotten out of the 6.2. From what I've heard, there's still a lot in there. I just haven't had the time and the money to get "to" it all yet.

Long term I'm thinking I might go for dyno tuning session. There's a awd dyno not too far from me and I might go that route instead of mail order.

The dyno would get you your best results, but I think you can see some gains with the Predator. My dad seems to think the Predator got at least another 20 or more hp out of the 6.2. I'm not sure it was that much. I do know, though, that before and after runs between my truck and his DTS Performance Edition ended differently. Before the tune, he could pull me, just a little, every single time... After the tune, I was able to pull him. If I remember correctly, we did that back in August, when I first got the Predator. I didn't get the duals and the CAI until November.

As far as my "butt dyno" is concerned, the Predator woke the truck up some. It was kind of like waking a sleeping giant, I guess. It's still a big, heavy truck. But, it just felt a little more eager, post-tune. With the duals and the intake, now, she's definitely more eager and ready-to-roll. I'd even go so far as to say she feels more peppy. Is there still more in there? I'm sure there is. I'd like to get more out of 'er, but I'm not sure how much more I'm willing to spend to do that.

I'm curious to see how she does on the road, this Spring. I'm overdue for a nice road trip. After I get the tires and wheels on, a couple of more cosmetic mods, and the snow starts melting, I'm planning to head north.. Definitely Colorado and maybe run up through Wyoming. I'm curious to see how she does on the road and in the mountains, this time. I'll definitely take the Predator with me, though, just in case I need to adjust anything. You never know what kind of gas you may run into OR how the thin air may effect it!

I want to get a couple thousand miles to get broken in. Unfortunately, that will only take me about 6 or 7 weeks

It sounds like you do a lot more driving than I do. If you don't mind my asking, what do you do that'll click off the miles that quickly?

Oh yeah, one more thing. Six speed seems confused at times. Downshifting too low when I lean into the throttle. I'm hoping it just needs to learn some as I'm only at 200 miles. I'm hoping when I punch it, it doesn't slam into first and start bumping the rev limiter

I'm starting to think some of the trucks' transmissions were tuned differently than others. Some people say they have to "really" get on it to get it to downshift between 35-70. To me, mine seems to downshift a little too quick. The shifting did seem to get better over time. It also seemed to get better after I put the Predator Tune in. I know the Predator doesn't touch the TCM, so it wasn't a direct effect. But, the transmission does seem to shift a little better now.. Maybe with more hp and torque, it doesn't "have" to downshift so quickly now? I'm really not sure.. But, I like it.

Oh! The rev limiter. Unless you're doing manual-mode shifting (and you don't upshift quick enough), you shouldn't hit the rev limiter, with it in full-auto mode. Actually, it shifts a few hundred RPM below the redline (and before it even hits peak hp, if I've read the charts right). So, don't worry about it downshifting on you and you hitting the rev limiter.

Also... And I know you didn't ask about this, but you did mention how the transmission shifts...

One of the things I've been doing is using the manual mode to set the maximum gear for it to go up to. Let's say I'm going to be going around 30, I'll put it in M4. If I'm going to be going around 40 or so, I'll put it in M5. I hardly ever put it in M6 or D, unless I'm on the freeway and I'm already up to freeway speed.

Doing that seems to cut down a lot on it having to come "way back down" through the gears to get to "go!" gear. Otherwise, if you leave it in D, it'll try to get to the highest possible gear, as quickly as it can, to maximize fuel economy.

I don't mind that too much. But, dangit, I wish they had it a little more balanced between fuel economy and drivability. It shouldn't be in 6th gear at just a little over 40, when "go!" gear is probably 2nd. That's too many gears to have to come back through before it can go, in my opinion...

So, that's why I do the Manual-Mode thing... Some other people have tried it and they seem to like it. To me, I think it helps the truck feel a little more responsive, too.

There's also a wealth of information from other people on here who have the 6.2/6-speed combo. I'm sure they'll have plenty to say, too.

If I missed anything, feel free to ask. If I know the answer, I'll let you know. If I don't know, I'll let you know that too!

EDIT : Wow, that was even long-winded for me!

Bish · December 28, 2007

Thanks for the lengthy reply. Sorry about the visual on the principals office

I own an Industrial Tool company and I drive all over the Chicagoland, southern Wisconsin, and Northeast Indiana. Throw in at least 2 cross country trips a year and I tend to rack up the miles. I like to go offroad motorcycling all over the country to sample the fine land that is the United States. One of the finest ways to see the country IMO.

I defintely agree with you on the "tuned differently comment". I know the Sierra Denali has 400HP yet the Yukon Denali is tuned for 380. I am reasonably sure the trans are programmed differently too because I would GUESS that the Yukon is tuned to be more "cushy" than the Sierra.

Also fully agree with you on the tire issue. I NEVER take a chance on having a tire blow up at high speed by exceeding the rating. That would be ugly! But then again, with the right equipment on the right road with the right conditions, noting wrong with a little high speed run IMO.

I'm hoping the trans is doing some adaptive learning to my driving. I know in my Tahoe, if I reset the memory, the thing would never downshift unless I floored it. After a thousand miles of driving it would downshift with half throttle. I'm guessing if figured out how I drive and figured I'm going to mash it do it might as well shift.

Bottom line I'm going to have to experiment for a while. Thanks for your comments, I appreciate the input.

Darkanion · December 29, 2007

No problem! Glad I could help!

The last several years, I've been trying to take at least one "good" road trip each year. Some years, I can squeeze in two. I've mainly focused on National Parks and then roaming around the country-side of wherever-I-end-up to "see what the people who LIVE here see every day." It's been interesting... You can click off a lot of miles doing it, though...

I have about a 2 mile commute to work. But, when I traded the '04 TSX in on the '07 Sierra Denali, it had over 65k miles on it. That's not a lot in comparison to the #'s you're talking about. But, for a car that didn't have to drive a long-ways every day, it sure clicked off the miles quick when I could get away from the office for a few days or a week or more.

Well, I'll let you get back to doing whatever it was you were doing. If you have any other questions, let me know and feel free to ask, others. There are a lot of helpful people around this place. That's how I learned a lot of what I've learned, since getting my truck in late May. Reading what others have asked and said and asking some questions myself.

ChrisNJ · December 29, 2007

Bish, I've had my S.D. since march with 6sp issues. I don't like how it upshifts too early, but really disliked how it wouldn't downshift properly. GM just came out with a TSB for it. I just got it installed but don't know the results of it yet as the truck is parked while I'm on vacation. It seems better with the 50 mi. i got to put on it. Do a couple searches, as I have written a lot about this subject. I don't know of any tuner yet for just the 6sp and doubt I'll go that route anyway. The truck is the best I've owned. I too do a lot of highway cruising for work and play and it is a pleasure.

What kind of riding do you do. My son and I do harescrambles and enduro's in NY/NJ/PA. ps: the SD tows our 7-8K toyhauler pretty well, better than my old 6.0's and comparable to my old 8.1's.

Bish · December 29, 2007

Bish, I've had my S.D. since march with 6sp issues. I don't like how it upshifts too early, but really disliked how it wouldn't downshift properly. GM just came out with a TSB for it. I just got it installed but don't know the results of it yet as the truck is parked while I'm on vacation. It seems better with the 50 mi. i got to put on it. Do a couple searches, as I have written a lot about this subject. I don't know of any tuner yet for just the 6sp and doubt I'll go that route anyway. The truck is the best I've owned. I too do a lot of highway cruising for work and play and it is a pleasure.
What kind of riding do you do. My son and I do harescrambles and enduro's in NY/NJ/PA. ps: the SD tows our 7-8K toyhauler pretty well, better than my old 6.0's and comparable to my old 8.1's.

Yeah, I realize it is a relatively new trans and will likely get updates as time goes by. I think they are tuning more for mileage than anything else. Give the tuners some time and I bet they will have other options.

As for riding, from about 20 years old to about 34 years old I lived in New England (Mass) and ran the NETRA Enduro series. Even rode the Beehive in NJ once. Moved to the midwest about 8 years ago. Riding schedule sucks out here compared to NE so I've found a few buddies that like to road trip. We alternate driving/flying. I drove with trailer and 8 bikes to Colorado a few years ago and my friends flew in for a weekend of riding. One guy goes to Phoenix every Feb so the rest of us fly down for a weekend or two of riding. Makes for a nice compromise when you only get stuck driving that crew every other year or so.

I find myself less interested in racing and more interesting in exploring the less inhabited spaces in the good ol USA. Ride a KTM 450exc. Can't wait to tow with my Denali!