1964 GMC 3/4 ton build :D

[sdwolff98]

Been a busy critter last few days getting the harness rebuilt and ready to install in the truck. have a few things left to finish up in it but turning out very nicely. I am relocating the dimmer switch to a relay unit on the fusebox and setting up a dash switch in the dashboard for the dimmer circuit as we speak waiting on a few parts to come in for it. Also got the malfunction indicator lamp set up in the harness as well. keep installing and removing the harness as each section of connectors are completed to look at the next set along the line. Thinking on the old air harness doing a SC button like on the newer vehicles and try and turn it into a blend system instead of how they have it rigged up. More to come on that one lol .

here are a few pictures of the harness rebuild and mod.

Sean

[sdwolff98]

the final steps in rewiring and reworking the harness is to do something completely new for a firewall junction that does not involve that nasty icky sticky connection grease lol. Going through the local salvage yards has yielded a few nice lil parts here and there and some fantastic ideas for fuel injection fuse box assemblies. here is the old firewall connector and its replacement part I found in a early 2000's oldsmobile car in the engine compartment. with a little digging was able to secure a pass through mount for it from an electronics supply company .

Sean

[sdwolff98]

and last but not least started tearing down the terrain console to get the wiring out for modification and prep for the tap shift and lights hook up along with a few other things in it as well . I got rid of that nuisancy shift lock assembly from the shifter as I found they can only handle 0.5v on the micro switch so I did away with that pia lol . Going to be working on the tap shift button and see ifs its current out put matches that of the 2006 shifter assembly out of the trucks. since my truck is a high hump I wasn't able to make the front pocket assembly work so I am working on a filler panel and ac vent mount spot where the console will meet the dash still more work to be done on it.

Sean

[sdwolff98]

been busy last couple weeks making parts lists gathering things up lol and working on the wiring harness. Got the resistor values for the 2006 truck tap shift assembly and I am now waiting on the needed resistors to come in. One of them is a ruddy bugger to get so being patient and waiting for some test samples to come in from some resistor companies it sucks I have to wait 7 weeks. Local circuit board company is going to swap out the resistor in the terrain shifter handle. luckily the 06 trucks and 11 terrain use the same circuit wiring for the tap shift setups. got a little more done on the wiring harness the dimmer relay is in place now and I am in the search for a dash lighted led button for the dimmer switch to replace my cigarette lighter in the dash. all of the wiring circuits are in place just have to gather the lil odds n ends for them to start getting it ready to finalize and install it. Firewall connector/bulkhead is almost finished. I just have to lay in some aluminum plate for it and mill it out to the right opening size. Last but not least WOOOOHOOOOOO its here on a pallet 2006 Allison 6 speed from a big block truck hehehe will be playing with that once the engine is out of the machine shop with its stroker kit and ls1 hot cam setup. looks like the trans will clear the body but will post pics when I get to that point in the installation.

Sean

[sdwolff98]

here are some pics of the Allison transmission. I will have the 8.1 harness with Allison harness in next week. Also Monday hopefully getting my vortec max covers in for the 6 liter.

Sean

[sdwolff98]

welp got my engine covers in yesterday too sweet brand new through gm parts direct 115$ also Friday will have my cruise control switches and the remainder of my interior harness connectors in hand to start wiring them in. going to be putting the harness up in the cab and routing the wires for there final cut off and wire in. nother week or two will be ready to tackle the under hood and body wiring on the outside of the truck. then start saving my pennies for the engine parts. hunting for a set of the emblems in the second picture if one of yall know where a set is reasonably priced not like the dudes on fleabay that think they are made of gold. I want another set for my engine covers like I did with the L92 engine I had previously

Sean

[Captainfab]

You continue to amaze me with your electrical abilities. The drivetrain is going to be awesome as well. Keep up the great work

[sdwolff98]

Capnfab,
lol I started a ls engine rewiring business on the side recently. I have built and rebuilt this harness so many times it is where I am asleep and able to do it. Going to posting up some pics next week of the cruise and dimmer relay switch assemblies .

Sean

[sdwolff98]

Well got a few more things done in the wiring of the interior of the truck. I finally got all the switches in for the dimmer and cruise control circuits and go them ready to install. still have to drill a couple of holes in the dash for the cruise control switch assemblies but it is going to turn out nice looking.

Here are some pictures of the switches I found they are gonna be cool when installed.

Sean

[sdwolff98]

And on to other things did some talking with several ls performance shops about the 6.0 engine before I started dumping money into it. Come to find out it was not going to work for the Allison without a large chunk of money for a turbo or supercharger 11:1 compression etc so I sold it off at a slight profit and got something with both factory capability and enormous build potential after doing some reading on a nice build thread on performance trucks forums hehehehe. Enter the vortec 8100 496 cubes picked up one cheap at a local salvage yard. The heads are in the shop right now since GM thought 8 mm exhaust studs would be quite fine in the head NOT!!!! 3 of the broke flush in the block lol. So they are getting repaired as we speak. Going to go back with a set of arp head studs and get it all back together next week. Got the short block and Allison in the truck and it fits decently had to pull the engine forward on to the 6 cylinder mounts on the frame and may have to do alil radiator relocation but will know more when its assembled and in completely and the nose is back on. I am going to have a friend section the trans cross member a slight bit to get the Allison mounted in the rear which will give me 1/2" clearance on the floor pan. the bell housing on the Allison wasn't going to clear the floor hence the 6 cylinder mounting spot. and it cleared just find from that point back. Also the truck blocks have both traditional and the duramax style engine mounting bolt holes to work with

Sean

[Captainfab]

That's interesting. I did not know that the 8.1 had provisions for the earlier engine mounts.

I don't mean to pee in your Wheaties, but I would not use that style engine mount with that engine. I doubt those will stay together long with the torque output of that engine. If those engine mounts come apart, and they will, the engine will be free to jump around. I much prefer the '73 and up engine mounts. They are a much stronger design, and will not allow the engine to move very far. To install the '73 + mounts, all you need are the frame brackets from a '73-'87 C20 or C30. Then the 'clamshell' that bolts to the engine , the thru bolts and the engine mount itself.

I bought some of those same lighted pushbutton switches on ebay a while back, for future uses.

[sdwolff98]

Hey Captnfab,
Yeah I am looking at that myself. I am also looking at the 67-72 big block mounts as well. I already trimmed my frame in the past for the 73-87 mounts so I can drop them in right in ifn needs be. Once I get the heads back on the engine I will know for sure which way to go the heads are a slight bit taller than the older bbc heads and it is a tall deck engine to boot. The rear mount of the head is pretty close to the firewall as it sits now. Yeah those switches are sweet looking wiring them into my dash light circuit so when I flip on the dash lights they will light up at night. I got the resistors in for the tap switch circuit will be getting those done next week. I am going to have to modify the factory cross member a small amount to get the th400 mount on the Allison to work it needs to drop about 3/8 of an inch for it to clear the cross member and the body. Friend of mine in Lynwood is pretty good at it so I am having him do the cut and welding on it then back to the powder coaters for its final coating. then on to getting the axle swapped over to the new housing and be pretty close to firing this thing off and maybe putter around the neighbor hood lol .

Sean

[Captainfab]

Yeah, the '68-'71 big block mounts would work too, but they are $$. The '72 BB mounts are even more $$$.

[sdwolff98]

Yeah they ain't cheap that for sure tge stands I can get locally pretty reasonable but the rubbers 185 a set. Will know more soon waiting on the head from the machine shop then bolt it back together and slip it all in n see where I am at.

Sean

[sdwolff98]

well got the transmission cross member modified so the Allison will fit turned out good 1/2 clearance on the floor board at the rear of the transmission. here are some pictures. I have taken the cross member apart to re powder coat it for its final assembly didn't realize how much rust built up behind those rivets. will be reassembling it with grade 8 hardware fine thread should be good enough that way.
Still waiting on the machine shop to finish the cylinder heads then can get new head bolts and upper end gasket set and get it reassembled and back in the truck.
Sean

[sdwolff98]

here are some pics of the Allison and the floor pan clearance.

Sean

[dwcardfan]

Your build looks good! I was wondering if you had the part number for the engine covers you got from gm parts direct. I would love to have a set for my build.
Thanks
Donnie

[sdwolff98]

I will get you the numbers for both the max and the 6000 covers when I have a few minutes at work today Dw.
Sean

[dwcardfan]

Thanks for the numbers Sean. Just got them ordered!

[sdwolff98]

Dw np any time

Sean

[sdwolff98]

well got a few things done have been waiting on money and parts for the most part lol . Got the head studs in today they are in place and lightly torqued down. Monday will be going through and torqueing them all the way in as per arp instructions say. Started on the gauge cluster lined out and got the indicator holes and cruise switch holes in place. Last week I worked on getting the truck engine harness stripped down and found some interesting ironies about the medium trucks I was not aware of.
I also opened up the firewall bulkhead spot to fit the Delphi bulkhead in place still thinking on ideas for the panel itself.
Here are some pics of todays work.
Sean

[sdwolff98]

Interestingly enough the medium truck harness in some very rare instances were installed on the 3/4 and 1 ton trucks as I found out when I got my harness in and stripped down. The truck I got mine from was definitely and 3/4 ton per the vin they sent me but interestingly enough the harness only had 2 o2 sensors wired in to it??? turns out the medium duty trucks hehe only were required federally to have 2 oxygen sensors in them lol not that I am complaining less holes in the computer connectors to have to seal up. Also the 8.1 engines do not use standard knock sensors they use some kinda funky connector style ones and I am working on tracking the particular pigtails down as we speak. BE WARNED ON THE MEDIUM DUTY HARNESS THEY DO NOT USE STANDARD COPPER JACKET WIRE FOR THE KNOCK SENSORS!!!!!. I AM NOT SURE WHAT THE DIFFERENCES ARE BETWEEN THE WIRE THEY USED AND THE STANDARD COPPER WIRE?? They used tefzel wiring 16 gauge on both the knock sensors for some reasons? what the differences between it and standard txl I am not sure?? Maybe someone can tell me as I am curious as to the reasons?

Sean

[sdwolff98]

Well while waiting on overtime to build back up at work started on a few other small projects since I had the materials in hand for them . First since I am going to a black carpet and interior to match my console setup. I pulled the rear cab panels out and I am in the process of recovering them with a different material then I originally used. I also at the same time made a new center panel out of one piece of abs instead of the three I had originally. here are some pics of the material and the new center panel I made out of some left over abs I had .

Sean

[sdwolff98]

and another pet project involves the marker lights irrational habit of falling out when I close the hood rotflmao. I put new sockets in and everything to no avail /sigh So I decided to see what I could come up with to make it so I could both service them but at the same time keep the dammed things in place lol. Well here it is and looks like it will work perfectly!! I took a couple of the extra tail light buckets that I had and cut the bulb mount and screw hole sections out and did a lil hammer work to flatten them out. The going back and forth several times got them where they conform to the GMC marker housing pretty well. I them when to the local oreillys and found a couple of tail lamp sockets with the foam seals on them. I attached the foam seals on the inside of the housing around where the buld mounts and and used some grey rtv to secure them in place. It is in the process of curing as we speak and I will be reinstalling them tomorrow. the other half of the setup is a set of new tail light pigtail harnesses from classic parts going to be working on those in a few days when I can get some 2 pin weather pack connectors together. the last pic is them housings I bought from oreilly to provide the seals for the bulbs.

Sean

[sdwolff98]

have not done much since I put the repurposed taillight mounts on my turn signal housings but I did however get a few more things for the 8100 while I was off on vacation. Got the heavy duty truck balancer in and also the GM service tool kit for the 8.1 vortec were here when I got home last night. Still have a few more engine parts to gather then slap it back together and reinstall it and the Allison in the truck and set it down for the final placement.
Got side tracked a friend asked me to rebuild a tpi unit and put a stand alone harness together for him then he backed out so trying to get it out of my hair and him paid back before retasking on continuing on smurf :/

next I have plans to get the tefzel wire and some other wire together after the engine is reinstalled and get to work on the firewall engine side of the harness.
Sean