I have a 1996 chevy silverado with a 4.3 vortec and manual transmission. What is the best or easiest vortec v8 to use to swap from v6 vortec to v8 vortec?

https://www.google.com/search?q=2007+Chevy+Silverado+2500+HD.+TCM+location

Diagrams and videos in the link

In general, a 2001 4.3 Vortec engine should be compatible with a 1996 Chevy vehicle that originally had a 4.3 Vortec engine. However, there may be some differences in wiring and sensors that would need to be addressed during the installation process.
It is recommended that you consult with a certified mechanic or an automotive specialist who can assess the compatibility of the two engines and provide guidance on any modifications or adjustments that may be needed to ensure a successful engine swap. They can also help you with any necessary adjustments to the transmission, exhaust system, and other components that may be affected by the engine swap.

very limited info generic answer no they will not need to do fab work ---mounts --harness--hoses--body work ---- if 2x4 or 4x4 driveshafts --- transfer case not simple- go to some of the s-10 forums some have info on swaps 8 from 6 ---8 from 4--6 from 4 -4 from 4 etc

Should be able to. Just make sure that if you have a std. transmission, that the replacement engine has a throw-out bearing installed. Or vise versa. And check your sensors, you might need to swap from the old to the new motor to make things work.

Chevrolet / GMC / GEO Transmission Look Up Table

www.autorepairmanuals.biz/page/372807

Blazer, 1993-, 4L60-E. Blazer, 1994 - Up, 6.5L V8 Turbo Diesel, 4L80-E. BLAZER/TRAIL BLAZER/JIMMY, 1995-2003, 4 SP RWD/4X4, L4 2.2L L6 4.2L V6 4.3L ...

Transmission Applications - GM Automatic Transmissions

www.gmautomatictransmissions.com/transmission_applications.php

Avalanche, 2001-06, V8 5.3L 5.7L 6.0L, 4 Spd RWD/4X4, 4L60E. Avalanche, 2004-06... Camaro, 1994-05, V6 3.4L 3.8L, 4 Spd RWD, 4L60E. Camaro .... Monte Carlo, 1997-05, V6 3.8L (W/S.C.), 4 Spd FWD, 4T65E. Monte Carlo ... Silverado, Sierra,1500-3500, 1995-06, V8 4.8L 5.0L 5.3L, 4 Spd RWD/4X4, 4L60E. Silverado ...

4L60E Transmission Rebuilt ' eBay

V6 and V8 take the same fuel pump.

yes same bellhousing

Different computer for sure, and probably a bunch of sensors, distributor, wires , starter, plug - ins, etc. The only way I would ever attempt that is if i had a whole perts truck to pick off of. You'd be far better off to fix the head gasket, sell it, and buy a truck with a V8 in it already, than to try that.

yes i imagine so. they are the same block but with different intakes.

You did not give your engine size or other information, but here is a list from the handbook...

Cooling System Capacity (Approximate)
VORTEC
4300 V6
Automatic 12.6 quarts (11.9 L)
VORTEC
4300 V6
Manual 12.9 quarts (12.2 L)
VORTEC
4800 V8
Automatic 13.4 quarts (12.7 L)
VORTEC
4800 V8
Manual 13.7 quarts (13 L)
VORTEC
5300 V8
Automatic 13.4 quarts (12.7 L)
VORTEC
5300 V8**
Automatic 14.9 quarts (14.1 L)
VORTEC
6000 V8
Automatic 14.8 quarts (14 L)
VORTEC
6000 V8*
Automatic 14.4 quarts (13.6 L)
VORTEC
6000 V8
Manual 15.2 quarts (14.4 L)
VORTEC
6000 V8*
Manual 14.8 quarts (14 L)
VORTEC
5300 V8**
Automatic 14.9 quarts (14.1 L)
VORTEC
6000 V8
Automatic 14.8 quarts (14 L)
VORTEC
6000 V8*
Automatic 14.4 quarts (13.6 L)
VORTEC
6000 V8
Manual 15.2 quarts (14.4 L)
VORTEC
6000 V8*
Manual 14.8 quarts (14 L)

Crankcase Capacity (Approximate)
VORTEC
4300 V6
W 4.5 quarts (4.3 L)
VORTEC
4800 V8
V 6.0 quarts (5.7 L)
VORTEC
5300 V8
T 6.0 quarts (5.7 L)
VORTEC
6000 V8
U 6.0 quarts (5.7 L)

Fuel Tank Capacity (Approximate)
Short Bed 26 gallons (98 L)
Long Bed 34 gallons (128 L)
Chassis Cab 34 gallons (128 L)