40ben Yukon

[2kwik4u]

I know it's not the same motor, but I'm knocking down consistent mid 16's with the AFM on mine.

Been doing some reading on the fullsize boards. Lots of guys running the monster 6.2L have been swapping over to 3.73 rear gears. Lets the truck run almost exclusively in V4 mode on the highway. Reports of well into the mid 20's are easily found.

What gears are in the Tahoe?

[2kwik4u]

Originally Posted by mkgearhead

I found this video. Very interesting... https://www.youtube.com/watch?time_c...&v=pK-zC17-Kx8

Great info, but not much of a screen personality there

[mkgearhead]

Originally Posted by 2kwik4u

Great info, but not much of a screen personality there

Identical to all GM training videos. Same boring monotone blah blah blah.

[Hotwire]

Originally Posted by mkgearhead

I found this video. Very interesting... https://www.youtube.com/watch?time_c...&v=pK-zC17-Kx8

Preciate the video. Mine is probably due to lifter bore wear (ASSuming), but haven't really heard of anyone measuring bore diameters.. Looking at that oil pan anyone could probably assume a lot about that motor.. I could understand it being an oil leak @ the VLOM, but the gasket looked good on that lifter casting, and there's only 4 solenoids operating 8 lifters. I'd torqued the VLOM when I put it back together the first time, couple of bolts towards the front of the engine I could turn with my fingers. Thought torquing that down would have increased my chance of success. The chance that another lifter would exhibit the same failure is high, but it was the same damn one with a brand new lifter. I'd like to replace the engine but going to get my money's worth out of this ol girl. Will have to pull the trans at some point and do a rear main, it's leaking pretty good. Was hoping it was just the pan gasket. I'd gladly rebuild the engine but spooked about the bearings as I haven't seen many good stories of rebuilds.

You hear varied reports of mpg with it on/off. I was bracing myself waiting to see the avg econ readout start dropping. When it clicked from 16.0 to 16.1 my eye started twitching and I wanted to grab a sledgehammer and start wailing on something, but it's a crap shoot, right?

Originally Posted by 2kwik4u

I know it's not the same motor, but I'm knocking down consistent mid 16's with the AFM on mine.

Been doing some reading on the fullsize boards. Lots of guys running the monster 6.2L have been swapping over to 3.73 rear gears. Lets the truck run almost exclusively in V4 mode on the highway. Reports of well into the mid 20's are easily found.

What gears are in the Tahoe?

RPO shows GT4, 3.73s. The hybrid somewhat spoiled me on the extended V4 mode. This yukon bounced in and out of it like a spastic kid red lining on sugar. I could coax it into staying in V4 mode for a little longer distance if I tried but no where near as easily as it was w/ the hybrid. <-did I just friggin say that!?!? Between the extended oil changes and head bolt leak, this engine is long in the tooth. Still pushes the yukon around easily but you can tell it's a far cry from what it was. Thinking that is the reason it didn't have enough power to stay in V4 long, mainly at lower speed / level ground, or somewhat downhill on the highway.

If I could sell that jimmy I got outright I'd flip this for a newer/less mileage vehicle, but unfortunately the MIL has her sights on the jimmy and doesn't know when she'd have the money to buy it, so all the money I'd saved up / used is probably going to vanish.

[2kwik4u]

Originally Posted by Hotwire

RPO shows GT4, 3.73s. The hybrid somewhat spoiled me on the extended V4 mode. This yukon bounced in and out of it like a spastic kid red lining on sugar. I could coax it into staying in V4 mode for a little longer distance if I tried but no where near as easily as it was w/ the hybrid. <-did I just friggin say that!?!? Between the extended oil changes and head bolt leak, this engine is long in the tooth. Still pushes the yukon around easily but you can tell it's a far cry from what it was. Thinking that is the reason it didn't have enough power to stay in V4 long, mainly at lower speed / level ground, or somewhat downhill on the highway.

I suspect mine is still decent on power, but it does jumps into/out of V4 mode far too often/easily. I've debated on putting 3.73's in mine, but it's a costly upgrade that doesn't have a really good reason other than an attempt at better mileage, and a bit more fun factor. Too many other things going on to mess with it. I'm running the 3.42's now, and they have plenty of power to pull the boat. I can't imagine what these guys running around with the CC/4wd trucks with 3.08 gears in them. They have to feel pretty underpowered in general.

Interesting that the Hybrid would stay in V4 mode more often. I suppose it was calling on the electric motor to maintain speed under load then? That's a really interesting system, and I'm curious how it would do now with newer gen motors. Doubt we'll know unless GM gets in a pissing match with Ford over hybrid tech again since Ford is putting a giant battery in it's new F150. Read on the Ram eTorque mild hybrid system as well, that looks like a mess.

I'm rambling now......back o the Yukon thread.

[Hotwire]

The hybrid system would help keep the the engine in V4 mode for as long as possible depending on speed/temp/battery charge(miles). Reason I was filling up the #7 cyl with oil and smoking out people behind me when it would go back into 8 cyl mode. It would use the electric motor in the trans to recharge the battery during braking / V8 mode. The regenerative braking would put that truck on it's nose if you needed to, it had 160 some thousand when I got rid of it and still think it had the factory pads/rotors.. Best braking vehicle I had ever owned (sad to say). It would also use the electric motor for acceleration when you got on it, took a second to get everything lined up but it would pull. Between that and the aluminum high compression 6.0 it felt extremely nimble for its size, surprised a lot of people. There were a lot of electrical nannies that kept you from getting a really good pull out of it, but just getting a taste of it between 2000-4000 rpms gave you a smile. Like someone fog shot the engine w/ nitrous. I miss it, but not being able to get parts for it or info to work on it put a damper on it. Couldn't bring myself to hot swap parts or pay a shop to do work on it.. they would probably be hot swapping parts too.

[MPETE]

I WISH I could pull down consistent 16mpg numbers. Current F150 has the 6.2 and its a heavy S.O.B. too at over 6600lbs with me in it. Around town during the week is 12-12.5.
Highway is around 15-16 if I am really gentle. Just went to NC and back last weekend and dash said 15.3 total for the trip, but the last tank hand calculated was 14.8. I also was NOT being friendly with the gas pedal.
I suspect the custom tune I'm running has dropped my highway mpg a little bit. But the extra power is sooooo worth it.
Coming back from NC last summer, running ethanol free gas I was able to get high 18's out of it. I'm only running 87 octane E10 right now. I'd be curious to see what 93 would get me, but not curious enough to spend the money on it. lol.

[Hotwire]

Lol dammit man, you should have told me, could have brought out the chevelle!

Last 2 tanks have calculated out to 16.2 but readout on dash is staying at 16.1. It's quiet, oil pressure is good, and it's getting me from a to b pretty comfortably. Have to address the rear main at some point though, it's leaking, was hoping it was just the oil pan gasket.

[2kwik4u]

Originally Posted by MPETE

I WISH I could pull down consistent 16mpg numbers. Current F150 has the 6.2 and its a heavy S.O.B. too at over 6600lbs with me in it. Around town during the week is 12-12.5.
Highway is around 15-16 if I am really gentle. Just went to NC and back last weekend and dash said 15.3 total for the trip, but the last tank hand calculated was 14.8. I also was NOT being friendly with the gas pedal.
I suspect the custom tune I'm running has dropped my highway mpg a little bit. But the extra power is sooooo worth it.
Coming back from NC last summer, running ethanol free gas I was able to get high 18's out of it. I'm only running 87 octane E10 right now. I'd be curious to see what 93 would get me, but not curious enough to spend the money on it. lol.

Lots of threads on the FS Chevy Boards about getting just as good or better mielage from the GM 6.2 over the 5.3.......Interesting you are getting just slightly worse than I am with the 5.3.

Spend the money on a couple tanks of 93 with your regular driving habits. It's ~$15/tank for me at time of purchase. However, I've found that my mileage goes up just enough to make it $0.01/mi LESS expensive than 87 octane. Truck likes it better, I get slightly better mileage, and the total cost is comparable. I'll take it. It's worth investigating if you think it might be close!

[MPETE]

Originally Posted by Hotwire

Lol dammit man, you should have told me, could have brought out the chevelle!

Last 2 tanks have calculated out to 16.2 but readout on dash is staying at 16.1. It's quiet, oil pressure is good, and it's getting me from a to b pretty comfortably. Have to address the rear main at some point though, it's leaking, was hoping it was just the oil pan gasket.

I wish I had time. Didn't come down until saturday morning and had to be home for work beginning of the week. Plus Dad moved AGAIN, and now he's down in Pleasant Garden, which is a bit farther away from you now. Before he was only like 15-20 minutes down the road from you.