[Hog]

I just read a few threads over there and it was entertaining. There is one thing that aI keep hearing about the GEN 3 1997-2005 car(99-07 in trucks) and the GEN 4 2005-2014+ in the cars 2008-2013 in the trucks, engines.
The GEN 3 and GEN 4 engines were not specifically built for truck usage, the 345hp LS1 was introduced in the 1997 C5 Vette, and into the F-bodies in the 305hp Camaro/Firebird. The 1st truck usage of the GEN 3 engine came in the form of the 255hp KR4 4.8(replacing the GEN1-E 230hp/285lb/ft torque L30 Vortec 305) and the 270hp/315 lb/ft torque LM7 5.3L(replacing the GEN 1-E Vortec L31 350 255hp/330lb/ft torque) and was introduced in 1999 which is 3 model years after the GEN 3 LS1 was iintroduced in the 1998 Vette.
Then in 2005 the Vette made the switch to the GEN 4 400hp LS2 engine while the GMT800 trucks soldiered on with the GEn 3 285hp/295lb/ft torque 4.8 LR4 and GEN 3 295hp/335 lb/ft torque LM7 5.3l engine.
In 2008 Vette upgraded to GEN 4 LS3 with 436-430hp/428-424lb/ft torque LS3. The trucks, now designated as GMT800 finally got there new GEn 4 engines in the form of the GEN 4 295hp/305lb/ft torque LY2 4.8 liter engine, the GEN 4 315hp/338lb/ft torque 5.3 liter LY5 and the premium SUV's such as the Cadillac Escalade got the GEN 4 6.2L 403hp/417lb/ft torque L92 engine.

Fast forward to 2014-Now we have the advent of the GEN 5 engine with Direct injection and Variable Valve Timing. This is the 1st time in recent hostory where GM has dumped the latest high tech engines into the cars AND trucks at the same time. The brand new K2xx truck line gets the new GEN 5(named ECOTEC3 355hp/383 lb/ft torque 5.3 liter L83(327 cubes) engine and the GEN 5 420hp/460lb/ft torque L86 6.2 liter (376 cubes). They even snuck in a brand new V6 making 285hp/305lb/ft torque.
And the cars, specifically the new C7 Corvette Stingray with its GEN 5 455-460hp/460-465lb/ft 6.2 liter LT1 engine.

So while these engines and their architecture is shared between cars and trucks, in most instances, the technologies were usually installed in the car platforms roughly 3 model years before it was introduced into the trucks platforms. These GEn 3/4 engines work MUCH better in the car platforms than they do in the truck applications. Trucks require excellent off idle/low rpm torque and decent low-mid rpm power for accelerating will pulling. The GEN 3/4 engines simply do not have the off idle/low rpm torque that the older engines have. This is evidenced by the 4.03:1 1st gear ratios that are used by the newer trucks and cars to help to Band-Aid these issues. I think everyone can agree that the LT5 stands alone. It was designed with one single purpose, DOMINATION, and it did/does so in grand style, with big power, big potential, big revs and decent fuel economy all at the same time. The LT5 was THE engine to make all competitors take stock in their own performance powerplants, besting Chevrolets own "performance" V8 by 130hp in 1990 and by 160hp in 1993-1995 vs. L98 or 105hp vs. GEN 2 LT1. Surely THE Heart of the Beast which was THE King of the Hill.



Which brings me to a story about boat launch confrontation my lowly 1997 GEN 1-E L31 Vortec 350 5.7 liter reg cab shortbox 2wd GMC Sierra, had against a brand new 1999 GEN 3 LM7 5.3 liter Chev Silverado, and its inflated ego owner/operator. Mind you, I do understand that I was pulling under 1000lbs of Yamaha Waverunners with 2 place PWC(Personal Water Craft) trailer, a model that has a carpetted plank running down in between the 2 Waverunners. This lets you walk the entire ength of the trailer when loading, unloading. It was a Northtrail double place trailer
A very nice trailer, way out passed the width of my truck, not sure on weight, surprisingly
heavy for what it was, all steel, not an aluminum frame or anything,while this guy was pulling out a good sized boat, no idea on its weight, but it looked heavy, IMO too heavy to pull with a 1/2 ton.

In 1999 when the 270hp/315lb/ft 5.3 liter LM7 replaced the 255hp/330lb/ft 5.7 L31 in the 1/2 ton trucks/SUV platforms, there was an uprising of owners complaining of the lack of off idle/low rpm torque of the new GEN 3 engines as compared to the older 350 SBC's. Owners who used to pull their boats up ramps in 4wd, were having to engage 4Low in order to pull the boats out of the water. I was waiting in the boat launch lineup and a guy with a brand new 1999 Silverado 4x4 was bragging about how much more power his truck had vs. my OLD 1997 2wd reg cab shortbox. He was quite a bit older than me, I was 19 or 20 at the time, so he was talking down to me the whole time.
He said" Have fun getting that thing up outta the ramp with 2wd and those drag slicks, I have a tow strap that you can borrow when you get stuck". I didnt bite, I contained my mouth and just said "Thanks, hopefully I dont need it" I knew that the newer GEN3 engines do work well once you get the revs over 3500-4000rpm. He continues
"This truck has over 300hp bone stock, I'm gonna get a chip and get 350 hp". I replied "Are you sure about that, I thought only the 6.0 liter's had 300hp."
He said "ya, that's right, the 6 liter, that's what I got" (and then the classic response that EVERY wing nut that thinks they have something special uses) " I had to special order it, the saleman at the dealership told me all about it". I thought to myself, well this guy had GM install a 6 liter in his truck, and no one else, he must have connections. I didnt even try to get into the conversation about this magical 50 hp tune he was going to get.(sarc)

Off on a tangent,
(his truck was a 1999 Silverado LD1500 4x4, as such the largest engine that GM installed was the 270hp LM7, the 300hp LQ4 engine was only available in the 1500HD, 2500 and 2500HD with the heavier 4l80e transmission. It wasnt until 2005 that you could get a 1/2 ton 4wd truck with the 6.0 engine as part of the VortecMAX Performance Package, in 2004 you could get a 2wd extended cab truck with the 6.0 engine a 4l65e transmission using r.p.o. B4V "high perfomance" package aka VHO trucks or Texas trucks, only available in and around Texas, there were 513 or so of these trucks built-B4V got you, specific for B4V 20"wheels(different than SS Silverado),3.73 rear gear,8.6" 10 bolt rear, traction control, 345hp LQ9 6.0 engine, 4l65e trans, the Vortec High Output badges on teh front fender(dealer applied some are missing) and somemore stuff, for 2005 B4V- got the same, but was available in USA and Canada and it got the 14 bolt 9.5" ring gear rear axle assembly-much better axle for the more powerful 6.0 engine).
OK back now,

The guy backs his truck trailer down the ramp into the water, someone on his boat idles the boat up onto the rollers of the trailer about 1/2 way, while the truck owner climbed down the bed of his truck onto the trailer, they threw him the bow line which he connected the winch from the eyelet on the bow and brought the boat onto the trailer all the way. He then climbed back up the bed and got into the cab. He applies the brakes, looks up at me like he was about to show me how it's done as I was standing perched on the cement retaining wall right beside his drivers door, and shifts into drive, releases the brakes, and gives her some throttle and the truck trailer moves up a few feet and as the boat starts to come up out of the water, the truck stops. he backs up a foot, then puts her back in drive and then truck moves again then stops. Then he really gives it some throttle and it was like he was doing a brake stall, lots of straining, but no moving. I could literally feel his blood pressure skyrocketting, and after another back up attempt with another heavy throttle attempt, he finally selected 4 low and pulled his boat out of the water.

I get into my truck, back my double jetskit trailer in down the launch, my buddy drives his Waveblaster 2 onto his side, then he goes and gets my GP1200 and drives it onto the trailer. I put my 2wd shortbox into drive and start to move, we leave our waverunners running as we pull the truck/trailer out, because as I begin to pull, my buddy ensures the bow is against the winch stop then gives my waverunner some throttle and as long as water gets into the pump it helps to push the trailer/truck up the ramp. Then when out of the water, they each gets a quick bounce off of the rev limiter to blow the water out of the pump assemblies. Being 2wd the extra push helps, and there is always a ton of sand on the ramp so I usually end up doing a bit of a rolling burnout with the tires in the water. Traction was very limited that day as I had just bolted on a set of 325/50/15 BFGoodrich Drag radials on 15" x 10" chrome steelies the day before, but they were new, so they had the most tread, that they ever would. I should have swapped them off for more appropriate tires, but oh well. That was the 1st and last time I towed the waverunners with DR's. At 27" tall with the 4.10 rear gears and 3.06:1 1st gear of the 4l60e trans, for a 12.5:1 1st gear final drive ratio, made it fun while pulling up out of the water. Once the exhaust boom tubes came out of the water, it sound really good. I got a couple thumbs up and some "Yeaaaw's" from a couple bystanders. Once I have everything up out of the ramp, I pull up next to Mr. new Silverado in order to apply my 2 tie downs, attach the bow eyes to the winches , pull the drains out of the machines and do a quick circle check. Mr. 4wd doesnt say a word and as I am just about done my cicle check, I say "Have a nice day, see you next weekend".
He said "later", I could tell he was pissed", but I felt great as he was talking down to me about my older model 2wd.
We got in my truck and I manually selected 1st gear, and got wound her up to 3000rpm just creeping along at about 3000rpm, racking the pipes just cruisng at the beach. It was a great day.

I used to have a buddy that worked at one of the local GM dealerships, and the techs said that lots of people would come and test drive the new GMT-800 (99-07) 1/2 ton trucks with the 5.3 and we really impressed with the 270hp@5200rpm/315lb/ft torque@4000rpm. Compare that to the 255hp@4600rpm/330lb/ft torque@2800rpm Vortec 350 L31 that the 1996-99 GMT-400 trucks came with. The 5.3 had 15hp more, but at 600rpm higher with 15 lb/ft less with the torque peak occuring at 1200rpm higher. The 88-99 GMT-400 trucks are also lighter than the GMT-800 trucks when compared on an apples to apples basis. (88-95 TBI LO5 350 200-210hp/290-300 lb/ft torque, 88-95 TBI 305 LO3 had 170hp/260 lb/ft torque, then the Vortec engines with 8 intake manifold bolts ran from 1996-1999 in teh GMT-400 style trucks, and in the 3/4-1 ton trucks that GMT-400 style ran through MY2000) The GMT-400 trucks had a powerplant change in between MY 1995 and 1996 akin to the L98 to LT1 swap which occured in between MY1991 and MY1992 in the Corvette.

Of course during test drives the potential buyer will romp on the throttle to "see what she'll do". During such unloaded WOT test drives the truck felt OK, slightly less "omph" out of the whole but once the revs came up the power impressed them. But then upon buying the trucks, they get their trailers hooked up, and then they feel the torque loss. They are having to tow in 3rd gear and even 2nd gear in order to keep up in the power band.
Many complaints were made, some even went and swapped their new GMT-800 trucks wit hethir GEN 3 5.3, for 1999 GMT-400 trucks either 1/2 ton, or 3/4-1 ton trucks with their GEN 1-E Vortec 350 engines. Some swapped their GMT-800 1/2 tons with 5.3's for GMT800 style 3/4 ton trucks with the GEN 3 300hp@4800rpm/355lb/ft torque@4000rpm. Doing this forced the buyers to get the 4l80e with their high 2.48:1 1st gear ratios, vs. the 1/2 ton's 4l60e's with their 3.06:1 1st gear ratios, this trans upgrade occurred when going from 1/2 ton to 3/4-1 ton in both the GMT-400 and GMT-800 style of trucks.