6.0/4L80 swap into my 85

[Shiner10]

I just picked up a 6.0 and 4L80 out of a 2003 2500 HD.I will begin working on the harness soon to do the swap.

A couple questions,

It is out of a4x4 truck. Is there anything that will prevent this from working in my 2WD?

Will my factory gauges work?

I've seen a lot about changing radiators. Is this necessary and why?

Any and all input will be great!

Thanks in advance

[Tilt]

I'm getting things together to do this same swap in an 86. Picked up a LQ9 in an Escalade a few days ago.

The 4x4 4L80 can be converted to work, but not as is. I can't recall exactly what you would have to change to be able to use it.

Your factory speedo will not work. One from a 90-91 suburban/blazer/1 ton truck will work, they changed to the electrical signal instead of the cable.

I see a lot of people using the original 80's model radiators. The inlet and outlet are in the same positions so grab the rad. hoses from the 6.0 and your good.

[andrewmp6]

The trans you have to change out the tail housing and output shaft.Its a job a trans shop should do and i would get it rebuild while its there.Or sell the trans and buy a 2wd one,Which you should make a few bucks a 4x4 trans is always worth more then a 2wd one.

[Shiner10]

Good to know! I'd rather make a few bucks than spend em!

[slotard]

I'm hoping to do a similar project sometime, efi and overdrive sure would be nice.

[Shiner10]

That's no joke! My 85 has a 305 and a 3 speed auto in it. Mine looks great on the outside, but leaks every fluid type that goes in it! I can't wait to get started!

[slotard]

Mine has a decent 350 (the guy who built it says maybe 275 at the crank so a solid truck engine but not a smog dog) and TH350, so yours should be an even better upgrade than what I plan on doing. Mine's straight and surface rust only, but hardly pretty.

[Shiner10]

This is my baby. I've only had it for about 2 months now

[andrewmp6]

Does the engine you got have drive by wire or does it have a throttle cable?

[Shiner10]

It is DBW. I got the complete set up out of the donor truck for 1500 bucks. But now it looks like I will be selling a transmission

[Tilt]

I'm in the same boat. The Escalade came with an AWD 4L65e that I can't use.

[scottybaccus]

Visit my FB page below to see mine. I put a LQ4/4L80e into my '87 a few months ago. You can message me over there with any questions.

You can keep your radiator, electric fans recommended.
You can keep the side mounted A/C compressor on the LS motor, with the right mounts. Likewise with the truck oil pan. Mine work.
By far, the best fitting iron manifolds are made by Hooker, ARP bolts resolve the breakage issue
The trans you have can be converted to 2wd. That is worthwhile if it is really low mileage. It requires full dis-assembly.
Making factory gauges work is easy enough. Use your current oil pressure sensor with a thread adapter, use the 3 wire temp sensor from a '98 Camaro V8. The rest is unchanged.
Waterpump from a 2010 Camaro has driver side top neck. I used it with a '06 Vette hose. The thermostat housing points lower, and eases the lower hose, too. It requires re-positioning the idler ($26 kit from Dirty Dingo), then uses the belt from a Hummer H1 8.1L

[Shiner10]

That's all great information, thanks for the input. What did you do for your fuel setup?

[scottybaccus]

I wanted everything to be very OE. Having an '87, the tanks already had efi pumps. I just swapped in the correct pumps for the LS.
I would suggest you do the same. The '87 fuel pickup assembly is about $75 on RockAuto. A new tank with the correct baffle is another $80? The pump is $100. That's a nice, rust free, system that you can get parts for anywhere. Just retain the fuel rail mounted regulator and run both feed and return lines.

[GRADYS Performance]

You can use your original speedometer with a tailhousing like I have on my Suburban. You can see the swap in the Suburban section. You can PM me for details.

[guzzo82chevy]

So I been checking out these engine swaps for a while now am yet to see it done on a 4x4, is there a reason for this? Can it be done? I'd really like to try it in my 82 chevy!

[scottybaccus]

4x4 take-outs are more expensive. The swap can be tough to adapt to a transfer case, and you lose a lot of benefit if you only swap the motor. Swapping the whole drivetrain is expensive, and requires some competent engineering to do well. There is also a problem where the front diff is on the wrong side, requiring an axle swap. Most early 4x4s are solid axle, and donors are IFS. It's a big job.

[andrewmp6]

Scotty if its 4l60e any tcase off a 700r4 should bolt on it like a np208 or np241 or for the 4l80e you can get a adapter to run a np205 or dana 300.Then you gotta have to 2 driveshafts made besides all the normal swap parts it takes.