Anyone swap a 4.8 Vortec into a 40?

[bikersmurf]

Stumbled across a low mileage 4.8 Vortec V8 with all the wiring, Computers, and Accessories for a good Price... which got me thinking about EFI again... and a spare more modern motor.

But, from the MPG numbers I've seen for 4.8s in 4WD Silverado trucks, it might even get worse MPGs than my Sept. 69, 350. Could this be possible?

Anyone have any experience with a 4.8 Vortec in a 40? Torque? Driveability? MPG City/Highway?

I've seen reports of 13-17 MPG highway in a Silverado . In principle it seemed like a good idea, a smaller Vortec V8, but is this a crappy motor?

 

[1973Guppie]

for the cost of all the conversion stuff and time it is going to take to put it in there you might as well go with a newer gen 3 vortec 5.3, mpg is not going to vary too much between the engines.....

 

[74fj]

for the cost of all the conversion stuff and time it is going to take to put it in there you might as well go with a newer gen 3 vortec 5.3, mpg is not going to vary too much between the engines.....

What year did the third gen 5.3 come out? I know in 2007 when the 5.3 went with the afm for fuel economy they have lots of oil consumption problems(I own one). The 5.3 prior to that are good engines. The 4.8 any year is a good eng because they have never had afm. A 4.8 does not get any better mpg but some people love them because they have a shorter stroke if I am not mistaken and you can get insane amount of power out of them. I have seen them with stock bottom ends with 500 hp. I am sure that's not what you are looking for in a fj but I would not count the 4.8 out if you could get a good deal on one.

 

[hobbes]

I was thinking about the 4.8L, vice the 5.3L, strictly because it puts out less power. But 270 HP is still more than I'd need. But if it gets worse mileage (and has less power)...

http://www.pirate4x4.com/forum/moto...-3l-6-0l-turnkey-engines-starting-1995-a.html

 

[bikersmurf]

Point taken. How are the MPGs from a 5.3?

The motor I found is a 50,000 mile 4.8 Vortec out of a 2001. However, if it gets the same or worse MPGs than my carbed 350... Then what's the point. With a Quadrajet it's dead simple, runs smooth, gets 13-15mpg around town, and I've got as high as 17 mpg on the highway.

Oh yeah, and the complete package is $750 obo.

 

[thetoyotaman]

I had a 4.8 V8 in a 2WD Silverado and it was a great motor. No oil burning and I avg. about 17-18 mpg. It's just a destroked 5,3. That being said, a friend of mines 5.3 Z71 4WD could do about 19 on the same roads. I know cause I borrowed it once. But that might of been because the Z71 had 3.73's and mine had the 3.42 and mountain driving. Good motor either way. My 4.8 started better than any car I have ever owned. It could be -20 outside and it acted like it didn't know it.

 

[FLNewt]

Point taken. How are the MPGs from a 5.3?

I got about 20 going from FL to Asheville this summer with an '04 2wd 5.3.

About 13 on the way back, but I was pulling a cruiser.

 

[jaydufe]

I just bought a 2001 sverado 2wd for 400$ with the 4.8 which is goon gont o my 40 replacing the old 79 350 in there now .