Considering a 5.3 to 8.1L CI Vortec 8100 L18 swap for a 2007 Yukon XL 1500 SLT

ecliptic55

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Hi Everyone,

I'm currently considering swapping out my 5.3L V8 which has an ever-existing oil leak off the back of it to either a 6.2 Vortec or even possibly a bigger engine like the L18 8.1 Vortec engine. There's a business that "remanufactures" the engine (found here ) and it seems like it may fit? I'm also looking to replace my existing 4L60 transmission for a 6L80. I know that the 6L80 transmission pairs with the 6.2L Vortec, but at this point I'm not sure what transmission pairs with the 8.1L.

Why are you considering this drastic change to your ride??

Good question. The main reason stems from existing used prices for trucks with more pulling power. I'm considering around a $15k budget for an engine /tranny swap vs. paying $45k+ for a truck with 100k miles. I need to be able to pull my wakeboarding boat long distances (750 miles one way). The boat I believe is around 6500 lbs, but when I pull it with my current set up, the transmission get really hot (around 220 degrees plus). Its working really hard for only 45 minute trip to the lake.

Questions I would like guidance on:

- If I decided to go up to the 8.1L Vortec, would it even fit in a 2007 Yukon XL 1500?
- What transmission generally pairs with the 8.1L Vortec? Would it also fit in this vehicle? If customizations need to be done, what would they be?
- if I replaced the engine and transmission, will I receive the desired effect and be able to pull my boat long distances?

Thank you in advance for any information related to this potential project
 

97YukonNZ

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Yep
I reckon the 8.1 swap will be perfect!
Especially if you are pulling 6500 pounds 750 miles in 45 minutes to the lake.
Nice work! Hope the swap goes well!
:driver:
 
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swathdiver

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Hi Everyone,

I'm currently considering swapping out my 5.3L V8 which has an ever-existing oil leak off the back of it to either a 6.2 Vortec or even possibly a bigger engine like the L18 8.1 Vortec engine. There's a business that "remanufactures" the engine (found here ) and it seems like it may fit? I'm also looking to replace my existing 4L60 transmission for a 6L80. I know that the 6L80 transmission pairs with the 6.2L Vortec, but at this point I'm not sure what transmission pairs with the 8.1L.

Why are you considering this drastic change to your ride??

Good question. The main reason stems from existing used prices for trucks with more pulling power. I'm considering around a $15k budget for an engine /tranny swap vs. paying $45k+ for a truck with 100k miles. I need to be able to pull my wakeboarding boat long distances (750 miles one way). The boat I believe is around 6500 lbs, but when I pull it with my current set up, the transmission get really hot (around 220 degrees plus). Its working really hard for only 45 minute trip to the lake.

Questions I would like guidance on:

- If I decided to go up to the 8.1L Vortec, would it even fit in a 2007 Yukon XL 1500?
- What transmission generally pairs with the 8.1L Vortec? Would it also fit in this vehicle? If customizations need to be done, what would they be?
- if I replaced the engine and transmission, will I receive the desired effect and be able to pull my boat long distances?

Thank you in advance for any information related to this potential project

Supercharge the 5.3 instead. If she has 3.42 gears, put in 3.73s or 4.10s. Swap out the spindly 8.6 rear axle for a 9.5" semi-floater (AXN) found underneath RWD Denalis and Escalades of same generation, bolts right up. If no engine oil cooler or external transmission cooler, add those.
 

91RS

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No. Just do a 6.2L. The 8.1L is garbage. It's archaic, heavy, gets terrible fuel economy (and I say that in comparison to what a 6.2L can get), and will leak like a sieve. The 8.1L is rated at 340hp and 455 ft. lbs. The L92 is rated for 403hp and 417 ft. lbs. and has VVT. The 8.1L will also take a significant amount of work to get it in and working where and L92 will literally drop in in a weekend and drive to work Monday.

Really though, you're probably better off to just sell and buy a Denali that comes with the 6.2L and 6L already and then get all the other things you get with a Denali - mainly the better interior.
 

bigdog9191999

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No. Just do a 6.2L. The 8.1L is garbage. It's archaic, heavy, gets terrible fuel economy (and I say that in comparison to what a 6.2L can get), and will leak like a sieve. The 8.1L is rated at 340hp and 455 ft. lbs. The L92 is rated for 403hp and 417 ft. lbs. and has VVT. The 8.1L will also take a significant amount of work to get it in and working where and L92 will literally drop in in a weekend and drive to work Monday.

Really though, you're probably better off to just sell and buy a Denali that comes with the 6.2L and 6L already and then get all the other things you get with a Denali - mainly the better interior.


i have to agree with this as a whole. I wouldn't go straight to calling the 8.1 garbage, but my driveway is a little bias. the rest is spot on however. the 6.2 or even a 6.0 would be a much much much easier swap. but then your still dealing with the trans, i would think you would be better off with everything already installed, or even the 2500 chassis and brakes. for the cost of your 15k you could keep the truck you have and get a 2500 in good condition just to pull with and have the best of both worlds.


as for your current trans situation if you don't have a good trans cooler could do you wonders.
 

Foggy

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6.2 or 6.0 would be the easiest swap... You could do the 6L80E or 4L80E trans
with them to replace your weak 4L60E.. Or have your existing trans beefed up correctly.

Make sure to upgrade the cooling system and trans cooling...
Headers, Tune, will do wonders as well.
 

swathdiver

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I'm a big fan of the 6.2 but think the supercharged 5.3 would be more economical to acquire and provide the torque at towing speeds to not require downshifting to a lower gear.

The 4L80 is a beast with really tall gears. The 4L60 can be beefed up to 4L65 standards and handle that power all day long.

A 6L80 swap is quite a bit of work, from crossmembers, to clusters, shifters to BCM programming and on and on.

If the truck already has 3.42 or 3.73 gears, he wouldn't even need a gear swap because of the supercharger's torque but beefing up the rear axle would eventually become necessary.

The supercharger would also negate the need for long tube headers and an aftermarket exhaust though it would benefit from either.
 

Geotrash

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The quickest solution for the problem you’re describing is a better external transmission cooler. A Tru-Cool 40k is a great solution for the 5.3, in my opinion. You’ll be lucky to see 160° pulling your wakeboard boat.

Lots of people out there pulling heavier craft than that with the 5.3 and a better transmission cooler.
 
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ecliptic55

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Thank you all for the feedback provided! Its truly appreciated!

I hadnt thought about supercharging my existing 5.3, but for longevity of the vehicle Im thinking of at least thinking of upgrading to a 6.2. I was just curious if the 8.1 would also be a viable option. Doesnt seem like it. Also, thank you for the info regarding the gear ratios and rear axles to consider. Ill let you know how it goes!
 

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