ChevyTech77

I've said it before and I'll say it again........... Driving these 6.2l 1/2 ton trucks is like dieting, for me. I have as much trouble keeping my right foot out of it so that it gets good gas mileage as I do keeping myself from eating too many nice, big, jucy burgers with an order of fries. Maybe it just isn't meant to get good gas mileage and I'll always be overweight, who knows. I will say this though, quitting smoking after 18 years, was easier than both of those issues, for me lol.

Love the sound of mine at startup also. I'm usually remote starting the truck as I'm walking out to it, after work, and I've gotten many, many compliments from co-workers all with pretty much the same question shortly after or before they hear it, "What the hell is in that thing?" Blown 540 big block is my favorite response. LOL! On another note, pulled down 13.8 mpg on E-85 this weekend, unloaded, but 10.8 with my two place enclosed snowmobile trailer on the back with one sled in it. Best unloaded mileage I've had so far on E-85 and by god does she like to pull that trailer on that stuff, yee haw!

Do yourself a favor and just get a current 6.2. The new trucks won't be out for another 18 months and you're probably not going to want to buy a few year or two of an all new vehicle/engine combo. I won't. I figure that my '11 should be ready for replacement just about the time that the CK2XX's are all debugged. Kind of like how my '11 currently is.

Belly up, you say? Not really. Well, kinda. Quadrasteer supplier = Delphi.

Set the rear wheels straight and power it down. That's it. The rear wheels will stay straight as long as you don't hit something with them sideways, like bumping a curb. I've heard of some guys just pulling the rear steering axle right out of the truck and swapping a standard axle into it's place, as well.

I've worked on literally, hundreds of Quadrasteer trucks. Yes, every 15k the diff fluid should be changed. I have only ever used the GM fluid but from what I've seen it is just a GL-5 gear oil with friction modifiers in it. The only other adjustment is setting the rear toe which should be done during any wheel alignment. Oh and btw, if the rear steering gear does go out (and most always do sooner or later) there is not a replacement made for them anymore.

Not exactly the same comparison that you are looking for but my '98 was nearly the identical build (same gear ratio and tire size) and it got 10 mpg pulling the same exact load under the same exact conditions that my 6.2l gets 12.5 mpg. The '98 had a 5.7l in it. Pulled like an ox but still not as good as my 6.2l does.

So, you changed to a larger tire and you're going to come into a thread like this and tell all of us that are running stock tires, etc. that we don't know simple math? Game on, son. Try getting your vehicle properly calibrated for the tires your running. I'll send you my gas slips after I go 500ish mile round trip, next week, pulling my snowmobiles around and get 12.5 mpg with my 6.2, all the live long day. Oh and my dic, is within .01% of hand math. It favors the bad side, also, if you were curious.

Did you get a chance to ride around with him while he was pulling? I'm curious as to how that little guy pulls. There's not been any real reviews yet except from Ford fella's whom think the EB is God's gift to humanity. Unfortunantly no, I didn't. I did ride in it with no load and it feels very smooth and has a very similar pull as my 6.2 does by the seat of the pants feel. I offered to run him down the expressway loaded, on the way home, but he declined. Sissy. LOL.

My boss has an Escalade that he parks in the one car garage her at the office. Everytime he starts it up, it echo's like crazy in the tiny garage. Sounds incredible! Even batter than my truck and it has a Borla exhaust! My 6.2/L9H equipped Silverado sounds very similar and I love it.

Well, 400-ish mile round trip this past weekend, towing my sled trailer with two sleds in it (2500 lbs approx.) and the 6.2 pulled down 12.5 mpg with an average speed around 70 mph. That's with headwinds, my trailer being a brick wall (because of the way it's constructed) and through the hills of Northern Michigan. In case you're all curious, my buddies '12 EB F150 was pulling a slightly heavier trailer, with better aerodynamics, averaging 70 mph and he got....................9 mpg.

I'm pretty sure that the size of pipe was used for less backpressure but making a 90 degree-ish bend, right after the resonator, wasn't going to happen in that amount of space with that size of pipe, is my guess. And an educated one, at that.

Z82 trailering package, that I previously listed, contains the aux trans and engine oil coolers.

That's pretty much what I was saying in post # 222 but it's interesting to note that neither the Z82 nor the Z85 suspension packages show anything about any heavier springs. In the parts catalog there are only two different part numbers for leaf springs on 1500 series trucks (which I also find hard to believe but I can't argue with the GM parts catalog), NHT/HP2 and NON-NHT/HP2, that's it. HP2 = Hybrid propulstion system.

To expand on that............ Z-85 Suspension Package, Handling/Trailering, heavy-duty, includes 46 mm piston monotube shocks and 36mm front stabilizer bar 1 - Included and only available with (Z82) Trailering package on Crew Cab models. Standard on Extended Cab models. Z-82 Trailering Package for MYC 6-speed transmission, heavy-duty includes trailering hitch platform and 2-inch receiver, 7-wire harness (harness includes wires for: park lamps, backup lamps, right turn, left turn, electric brake lead, battery and ground) with independent fused trailering circuits mated to a 7-way sealed connector, wiring harness for after-market trailer brake controller (located in the instrument panel harness), (K5L) heavy-duty cooling package, (KC4) external engine oil cooler and (KNP) external transmission oil cooler My truck has the Z82 package, as do all with a 6.2l engine. That makes it even more interesting.

Straight out of the GM Dealership order reference guide - Max Trailering Pack, includes (L9H) Vortec 6.2L V8 SFI engine, (G80) heavy-duty automatic locking rear differential, (Z85) Handling/Trailering Suspension Package, (AXN) 9.5" (24.1 cm) hybrid rear axle, (GT4) 3.73 rear axle ratio, (P46) 4 - 17" x 7.5" (43.2 cm x 19.1 cm) 6-lug aluminum wheels, (QJP) P265/70R17 on-/off-road blackwall tires, (T96) fog lamps, (JD9) front and rear disc brakes and (Z82) Trailering package

Sure, there are differences between the NHT and Non-NHT rear leaf springs, this we all know. It is not that the NHT springs are wider, they are the same width, from what I've measured. I see that the Hybrid Silverado/Sierra's are also listed as taking the same springs as the NHT trucks so while there is no available spring rate information, I'd have to say that the increase is marginal, over the Non-NHT springs, at best. Believe it or not, most of the extra 1,000 in towing capacity probably comes from the gear ratio increase. That happens all the time.

Did some more light towing with my truck this weekend again and found that I can pull my two place clamshell snowmobile trailer in 6th gear without much fuss at all, at 75 mph and getting 12.5-13 mpg. Granted, the whole setup might only weigh 2200ish lbs rolling down the road but the trailer cap turns this thing into a huge windblock when you're rolling down the highway. Plus, northern lower Michigan is no slouch for decent grades and hilly terrain so although it did downshift to 5th a couple of times, the trans temp never scowered over 125 degrees the whole pull (100 ish miles one way). Again, very impressive seeing as how a friend of mine pulled a very similar trailer for a while (until he upgraded to bigger), with his '08 HD 6l and had to leave the 6 speed in 5th gear and got no better than 9 mpg rolling the same speed. Same goes for how my '98 use to pull this same trailer. While I would never think of trying to pull this trailer in 4th gear in the truck, it would pull it without issue or downshift, in 3rd gear all day long however, at that speed and engine rpm, 10 mpg was the best you were getting, period. 9, if you were bucking a headwind the whole way. Just more reason to love my purchase more and more.

NHT (Max trailering package) trucks DO NOT HAVE HD (referring to the HD Silverado and Sierra chassis group) springs. They have a slightly stiffer rate leaf spring pack, then the other 1/2 ton trucks yes, but they do not have "HD" springs The Gov-Loc differential does work the same in an "HD" and 1/2 ton truck yes. Different axle assemblies all together but yes, the differential workings are the same. NO 1/2 ton trucks sense '04 have had rear disc brakes unless they were a Vortec Max or Max trailering package truck with the 9.5" rear axle assembly.

Probably not far from the truth because the new gen truck engines will produce similar numbers while at the same time pulling down better mpg numbers as well. Wait and see is all we can do.

Mine certainly doesn't shut down at 92. More like 99 but not 92, for sure.

Pffff, 7 months old now but has 9200 miles on it. And I only live 2 miles, one way, from work. Can't keep my hands off it! LOL.

I would expect the L9H to run slightly better due to its intake and exhaust refinements. Even the littlest change there makes a huge difference in overall power and drivability.

Overview The Vortec 6.2L V-8 VVT (L9H) is one of the most technically advanced truck engines in the segment, with features that include variable valve timing and E85 flex-fuel capability. The L9H's balance of performance and efficiency is great airflow throughout. Intake flow was improved by straightening out and optimizing the flow path from the intake manifold into the cylinder heads, while the exhaust ports are also designed for greater flow. The 6.2L is the most powerful of GM's Vortec V-8s. It delivers exceptional refinement to go with brute strength, and advanced technologies such as cam-in-block variable valve timing. It was also developed for quieter operation, with virtually every system or component reviewed in an effort to reduce noise, vibration and harshness. Quiet features built into the engine are complemented by an improved engine cradle and mounting system. These help reduce vibrations transmitted through the chassis and into the passenger compartment.

L92 was available in the Sierra Denali's only, from '07 to '08. '09 to current model year pickups use the L9H. Both are 6.2l but the L9H just has some minor intake and exhaust improvements in both the manifolds and in the cylinder heads. Both engines had VVT but no AFM. Only the 6.2's that were installed in the Yukon Denali's and Escalades had AFM. I do not, however, believe the L92's had E-85 capability but I can't find 100% supporting evidence for that claim either so......