Thats my thinking too its only gonna see towing dutys maybe once a year if that. The trucks in NM at pattys mom and dads we only use it when we go visit.
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6.0 LS engine, who tows with one.
- Thread starter yellowK20
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Bring it up here I will put the 6.0 in it for you and then "test" it for you to make sure its alright!!!
Sounds like a plan lol
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In that case, a 6.0L will work fine for occasional towing but then again so will a Honda CRV. 
black dawg
1/2 ton status
If you really use it that little, is it worth the swap?
what gear ratio is this truck?
what gear ratio is this truck?
4.56's and yeah its worth it the 350 TBI runs fine its just not exciting
COCHEV
1/2 ton status
Ah, negative. Be glad to help give guidance from here though.I have been quite used and abused helping internet so called “friends” do 8.1L swaps over the past few years in everything from Corvettes to ugly truggies. Some guys are appreciative and others are flat out users then claim the knowledge came from them. I have figured out some of these guys are users and have stopped supporting them. If any of them are reading this and wonder why the emails and PM’s have stopped… A simple thank you and give credit where due would be appreciated, if that is too much to ask then they can elsewhere to get help. I should write a book and start charging for L18 swap info.
besides displacement, what are the main differences between the 8.1 vs the vortec 454? Was thinking the 454 might be a cheaper swap than the 8.1? my 97 is rated at 440 ftlbs and does real well pulling. 12-13 empty/ hwy.
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When it comes to swap cost, there really is no notable difference in money between a L29 Vortec 7.4L or L18 Vortec 8.1L outside of the cost and availability of the engine itself. Both the Vortec 7.4L and 8.1L can be found cheaply or very expensive depending where you live. To buy a harness, tune, fuel pump, lines, and installation accessories for both will cost about the same.
The ‘97 L29 7.4L is not rated at 440 lb. ft., it is actually rated at 410. None the less, the L29 is still a great engine. It is a hoss too not quite the hoss the 8.1L is.
1996-2000 L29 7.4L
290 HP @ 4,000 RPM
410 lb. ft. torque @ 3,200 RPM
2000-2010 L18 8.1L
340 HP @ 4,200 RPM
455 lb. ft. @ 3,200 RPM
On the surface there doesn’t appear to be much difference between the Gen V big block L29 or the Vortec 8.1L but they are completely different animals. The blocks are entirely different, cooling jackets are different, combustion chambers are different, internal oiling is different, heads are completely different, the 8.1L has 2 more head bolts per side and the LS type firing order for greater balancing and many more things I can't exactly remember off hand. The 8.1L also has a “dry” intake where no coolant flows through the intake itself. When you just eyeball the bare blocks themselves you have to look very hard to tell the difference between an 8.1L or Gen V. There are no common internal parts used between the 7.4L and 8.1L although you can use a PF1218 oil filter on an 8.1L if you wish. I know I do, because the PF1218 is bigger than the 8.1L oil filter.
Interest excerpt directly from GM Powertrain’s website:
After extensive analysis of competitors' engines, the 8.1L development team set a goal of 200,000 miles of useful life without major repairs--and then achieved it. The engine has been tested and validated to meet this 200,000-mile durability standard. Before it was ready for production, the 8.1L had to pass the ``Marine Dock'' test, in which it is run at full throttle for 300 consecutive hours, and a minimum of 1000 hours at full-throttle operation for truck applications.
The marine dock test is pretty significant because there is no other GM engine past or present that carries that certification. Nor does Ford or Dodge have those bragging rights. Could be because nobody bothered with this "Dock test" before either...who knows, but the dock test bragging rights is a big reason the 8.1L is a favorite of the marine industry for gasoline powered huge boats. VolvoPenta 8.1L 375 and the Mercruiser Horizon are both the same 8.1L as used in trucks other than different cam profiles, ECM calibrations and marketing.
I don’t have any tear down comparison pictures between an L29 7.4L vs. L18 8.1L but here is a visual compare of the cylinder heads. The L18 actually has smaller exhaust exit ports to achieve higher torque ratings at low RPM's. That is what GM Powertrain claims anyway.
Sorry, YellowK20….we really got off track on your thread
Sorry, YellowK20….we really got off track on your thread
No need to be sorry its all good food for thought, the main reason against the 8.1 in my book ( other then dealing with the Allison) is that there isn't as much aftermarket support readily available for them. that coupled with the frame mods and trans stuff adds up to more of a pain then I'm willing to deal with. pluss the price point is much higher I can get the escalde version of the 6.0 with low miles for about 2500 with harness and ECM I can't touch a 8.1 in that are for under 5000.00 there very popular for well engines down there.
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What? Okay, not sure where you are coming from with everything you just said. Go back and read my post #13 slower this time. The 8.1L does not require an Allison. Any GM transmission will bolt right up to it. I had a SM465 behind mine for the first 2 years then later swapped in a NV4500. A TH350, TH400, 4L80E’s, etc will all go behind one just fine. Hell, you can bolt an old powerglide to the back of one if you want.
Also, like I said several posts ago the 8.1L is easier to swap in over a 6.0L for the simple reason there are no chassis modifications that need to be done. At most you may need to add an ORD engine crossmember for the large oil pan clearance. The 8.1L uses the same engine mounts as any old small or big block. You can also use G-van or Workhorse 8.1L accessory brackets so the A/C compressor can be moved up high like an L29 7.4L where there is no frame interference with the A/C compressor like there are with an LS engine.
What aftermarket support do you need? A stock 8.1L is an animal right out of the box. Sure there aren’t as many hop up parts for them but there is no need to buy any of that crap. A bone stock engine on tweaked calibrations will perform just as well, if not even better and more reliable than older engines that have been bored and whored with big bumpy cams.
WOW that cost is too high for the 6.0L and way too high for the 8.1L
Down here both go for around $1500 to $2000 for used ones.A 6.0L is still a good swap, it is just low on power for a truck of that size and much more challenging to install than an 8.1L. A Escalade 6.0L will definitely be a huge bump in HP but you will be disappointed how you have to beat on it to get any power out of it and how well it won't pull a greasy string out of a Coke bottle.
2500 is wrecking yard price, I can get them cheaper if I shop around but thats the anydayoftheweeknormalguyofthestreetprice 
I know I don't "need" the allison but I'm a newb when it comes to this stuff so It would be "easier"
I didn't know about the other accessories drive every 8.1 swap I've seen has had some butchery to the frame to accommodate it, (learn something new everyday)
I guess the "real" problem for me doing an 8.1 is the unknowns and my bad experience with them in the trucks they came in.
I know I don't "need" the allison but I'm a newb when it comes to this stuff so It would be "easier"
I didn't know about the other accessories drive every 8.1 swap I've seen has had some butchery to the frame to accommodate it, (learn something new everyday)
I guess the "real" problem for me doing an 8.1 is the unknowns and my bad experience with them in the trucks they came in.
to put this all in to perspective, I currently tow with 90 V3500 with a banks turboed 6.5 with a few mods . so like I said i'm not looking to race it our pull 80,000 lbs of chickens at 90mph over Wolf Creek pass . 
http://coloradok5.com/forums/showthread.php?t=256911
read the coments here @ ck5 before you pass judgment on his article. 1 guy says diy or ord mounts and ord crossmember and headers with kodiack brackets it drops in .
read the coments here @ ck5 before you pass judgment on his article. 1 guy says diy or ord mounts and ord crossmember and headers with kodiack brackets it drops in .
COCHEV
1/2 ton status
Awesome information, Larry 
I think all engines should be up to the task of 200k with no major repairs.
didn't the early 8.1s go behind a 4l80e in the avalanches and what not?
my ol' 8.1 was a gnarly beast. I sorely miss it. I've managed to have big blocks through both gas crunches
anyways, back on track...sorta
I think all engines should be up to the task of 200k with no major repairs.
didn't the early 8.1s go behind a 4l80e in the avalanches and what not?
my ol' 8.1 was a gnarly beast. I sorely miss it. I've managed to have big blocks through both gas crunches
anyways, back on track...sorta
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Yes, if you looked at the 8.1L swap on at hotrodlane . com by the Wyotech instructor, YES…you’re right. That guy hacked up the frame and bunch of other stuff that didn’t need to be done. Apparently, you have never looked at my 8.1L swap pictures into my K10. Not one ounce of any hacking. The engine bolts right in with the proper research and use of parts. I pulled a 454HO out and stuffed an 8.1L in its place in one day then spend the next few days making connections, routing the harness and creating the fuel delivery system. No drama at all
Sounds like you have been reading a bunch of pirate4x4 garbage. to put this all in to perspective, I currently tow with 90 V3500 with a banks turboed 6.5 with a few mods . so like I said i'm not looking to race it our pull 80,000 lbs of chickens at 90mph over Wolf Creek pass .
A turbo 6.5L isn't exactly a slouch though. Not a Cummins or Dirtymax, but not too bad. A 6.0L would dissapoint you after being used to a Turbo 6.5L Yeah, pretty much every bit of insight that people said in that thread came from me in emails I exchanged with them before becoming active on CK5 again.
y5mgisi
1 ton status
Stupid ck5... Now i REALLY want an 8.1!
COCHEV
1/2 ton status
An 8.1 sure would look swell in that GMC of yours
Sure would, especially with my name on the title........
