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Its time for the 5.3/4l60e to meet the 86 k5/np208

KansasTwister

KansasTwister

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well, since i want to make my k5 a daily driver, ive been tossing around the idea of a more modern drivetrain. Not too long ago i learned the 4l60e would swap the 700r4 perfectly, and i had already known the potentials of the 5.3 genIII motors, as i learned more about them i wanted one more and more. For the last five years the k5s had no motor and not moved under its own power.

The motor itself is from a 2004 silverado, 60k miles complete takeout (Accesories and computer). 600 (i got a screaming deal).

http://cgi.ebay.com/ebaymotors/ws/e...akeTrack=true&ssPageName=VIP:watchlink:top:en

Ill be using the above motor mount adapter plates (Already got a pair in my buddys 67 c10 that worked flawlessly when we dropped a 27k mile 5.3 in)

I still havent picked out the trans, but it will be from a similar year 4l60e 4wd.

Eventually id like to swap for a np241 t case (89 mechanical speeedo to save form having to change cluster out). Summit used to carry the vss adapters, i believe i found the same thing on jegs. (summit had the option for tbi or ls1 style motors, but this one doesnt say how many beats per mile it is)

http://www.jegs.com/i/Caspers+Electronics/182/102049/10002/-1

Fuel system, im planning on using a 87-91 blazer tank with a newer fuel pump (if im correct, this will allow me to use stock gauge still). For regulator, im going to use vette style dual in one out mounted at rear of vehicle and just run a single line forwards. (not sure what all fitting or adapters ill need for this)

Ill probably keep the thorttle by wire setup, since its not hard to install the pedal in my 86, but would be a pain to try to switch it to cable style.

Airconditioning can be worried about later, although ive seen a third gen guy using stock style ac compressor via custom bracketry. And i dont believe i should have any problem with the genIII truck accesories or oil pan correct?

http://www.thirdgen.org/techboard/ltx-lsx/487936-ls1-700r4-swap-into.html

For the harness, theres a local guy who simplifies and extends and reprograms for your vehicle the wiring harness, $400

I know im going to need other things like hoses, possibilty a radiator, lots of patience when wiring, im going to put new brake pads shoes and hoses (since my k5s been sitting on grass for 5 years now without a motor).

Some of the concerns i have are gonna be my 32s and 3.08 gears (id prefer 3.73s). Will this make overdrive useless?

Any thoughts or opinions you guys have let em rip, im all ears. Im new to this tech, so if theres a better way im missing fill me in. I dont think the 5.3/4l60e/np208 will be a bad daily driver/commuter combo, i know its not gonna get the same gas milegae as a honda, but should be better than my old 350 quadrajet and 3.55 non overdrive 77 pickemup. Ive probably missed covering some things, but i think ive got the big issues covered.
 
Oh, id also, if possible, not like to have driveshafts made (since im not going to be lifting it, at least at this point in time). So would the 4l60e keep the t case right where it is now? Thats one of my biggest fears with this swap.
 
Better check with engine swap laws in your state if you have to pass emissions testing. Here in California you are allowed to upgrade the engine BUT the engine must be the same year or newer than the vehicle it's going into and the engine must also be the same size or LARGER. If your 86 blazer came with a 305 you're ok if the same law applies but if your blazer came with a 350 you're screwed.
 
I'm "pretty sure" a 4l60 and a 700r4 are the same, only one is a further evolution (newer). I do believe the dimensions are the same....
 
no emissions here in kansas (at least yet, if they start im going to stick to pre 75 gms, my 77 longbed is emission free from factory and thats the way to be)

Thanks for the confirmation on the 4l60e, from what ive heard its just the modern 700r4 thats actually worth using (ive heard bad stories of stock 700r4s, why i havnet really done anything wtih my 86 yet).


Oh, what about column linkage, another issue i need to think about.
 
amazed i havent heard any more opinions on this issue, if all goes well im picking the motor up this week, then trans, slowly by slowly piece i piece ill get there, may take a while but ill do it once and do it right.
 
The 5.3/4l60e swap is a good idea and I think you'll be happy with it of you do it right. Make sure you take your current budget and at least triple it.

The motor mount plates will work just fine and save you some work.

The wiring harness is a fair amount of work and is quite intimidating if you've never done anything like it before. May be money well spent to have someone with experience clean it up and label your connections for you.

The fuel system is fairly simple to set up, just get a 87 up sender and use a 96 vortec pump and install it in your current tank. Use a newer Corvette fuel filter with a built in regulator. Simple one line connection to the motor.

Your current shifter linkage should work fine with the 4l60e.

The 96 up 4l60Es use a 6 bolt pattern (700r4s and 93-95 4l60Es use 4 bolt) but can be easily adapted to your current adapter and t-case.
http://advanceadapters.com/product/2322/50-0405.html

You'll notice that adapter also has a provision for VSS. You MUST have a 40 pulse signal for the transmission to shift properly, this adapter is by far the easiest way to get a 40 pulse signal and still keep a mechanical speedo.

The truck exhaust manifolds usually won't clear the frame without some cutting, especially on the passenger side.

A/C will require custom hoses to be made, the 5.3 compressor will just fit inside the frame rail with no mods.

Make sure to get the throttle pedal/sensor, the throttle control module and wiring if you get an electronic throtlle control motor. In fact make sure you get everything you can from the donor truck especially the starter, alternator, a/c compressor, MAF sensor/air box, etc, etc.
 
Im gonna have a local guy do all the wiring for 400, takes him 2-4 weeks to get it all done after you give him harness. Ill probably stick with fly-by-wire setup.

I thought the 87-91 tanks had built in baffles, figured they would be better to use than my 86 tank with a newer sender. The rest of fuel system you described is how i was planning to do it, local guy puts these motors in old camaros and such, so i was going to have him help me buiyng eveything i needed for the fuel system.

I was hoping not to have to move the transfer case to save from having driveshafts modified, wont that adapter make the 4l60e longer than the 700r4 case? im not sure how different they are. In that case i may need to find an older case from 93-97 right? wonder how complicated that will be to mate up to the 5.3, haha.

For vss i was going to get an inline adapter that puts out 40 pulse, just goes in the speedo line, keeps from having to change cluster or buy gauges and bolts right in and should work fine id think.

AC can always wait to be done, its september now, wont need it till next spring/summer. And then i will probably switch out the stock componets for more efficent and space saving aftermarket pieces.

I know im gonna be dumping probably around 2k in this swap, and im okay with that. I need a good daily driver, and this will make the k5 perfect for what i need.
 
Other than acquiring the '90-91 NP241 (which is common) IMO I'd just spend the effort to swap to the electric speedometer/DRAC/VSS.

Mechanical speedo is not a problem, since the NP241 donor will have all the pieces you need.

Since you already want a 241, go with the more common two-year variant, and get it all out of the way at the same time.

On gearing, I'd look at what the trucks were coming with at the time the motor was made, and use that as a guide. The amount of power those motors made was such that they should be able to motivate that truck with numerically low gears without shifting too much, as long as much heavy towing isn't in the future.
 
KansasTwister said:
Im gonna have a local guy do all the wiring for 400, takes him 2-4 weeks to get it all done after you give him harness. Ill probably stick with fly-by-wire setup.

I thought the 87-91 tanks had built in baffles, figured they would be better to use than my 86 tank with a newer sender. The rest of fuel system you described is how i was planning to do it, local guy puts these motors in old camaros and such, so i was going to have him help me buiyng eveything i needed for the fuel system.

I was hoping not to have to move the transfer case to save from having driveshafts modified, wont that adapter make the 4l60e longer than the 700r4 case? im not sure how different they are. In that case i may need to find an older case from 93-97 right? wonder how complicated that will be to mate up to the 5.3, haha.

For vss i was going to get an inline adapter that puts out 40 pulse, just goes in the speedo line, keeps from having to change cluster or buy gauges and bolts right in and should work fine id think.

AC can always wait to be done, its september now, wont need it till next spring/summer. And then i will probably switch out the stock componets for more efficent and space saving aftermarket pieces.

I know im gonna be dumping probably around 2k in this swap, and im okay with that. I need a good daily driver, and this will make the k5 perfect for what i need.
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If you use a 4l60e you petty much have to use an adapter. The adapter I showed you isn't very thick and shouldn't cause any issues with your drivelines. You'll spend more money buying parts to make an older 4l60e work with the 5.3l. Just get the newest trans you can afford, buy the adapter and be done. If you do it any other way you WILL regret it.

The in line 40 pulse sensors are kind of problematic when used with electronic transmissions, steer clear of them. You need a fixed tone wheel and sensor for a consistent signal. The adapter I showed you or a later 241 dyeager mentioned are the only reliable options. Do yourself a favor and don't waste your money on an inline sensor.
 
I'm currently doing the same type of swap in my 75' K-5.
Just got my 4l60e back from the shop AND I'm wanting to mate it to a 241.
But I noticed that the 4l60e and the 241 are both a 6 bolt patterns.
Is this something Advanced Adapters can fix or is this a GM part?
If so, what years should I look for?
 
A factory adapter will do the trick. Just get one for a 2000 or so half ton pickup, should be around 70 dollars at the dealer.
 
if u convert over to the np241 transfer case from the NP208, can u use the np208 drive shafts or u have to have some made or from another vehicle?
 
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