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GMC-YA68 03-16-2015 11:55 PM

1972 Jimmy + 5.3/4L60E/NP205
2 Attachment(s)
Well I guess the time is now. The plan is to do a 5.3/4L60E and mate the stock t-case to it. I have an 04 pullout with only 55k that a buddy of mine ran into recently. Ran a carfax on the truck it came out of and all seems legitimate. Picking up the engine, tranny, harness, ECM this week.

Started an early morning tear down last weekend with my lil bro... Cheers and most importantly thanks for all the info gathered here and ls1nova71 for already answering numerous questions that I have thrown his way!!

Ridnhi 03-17-2015 12:19 AM

Re: 1972 Jimmy + 5.3/4L60E/NP205
In for this, would love to do same to mine. Nice rig!

GMC-YA68 03-17-2015 12:22 AM

Re: 1972 Jimmy + 5.3/4L60E/NP205

Justin@EntropyRad 03-18-2015 03:56 PM

Re: 1972 Jimmy + 5.3/4L60E/NP205
looks like a beast!

chesafreak 03-18-2015 08:24 PM

Re: 1972 Jimmy + 5.3/4L60E/NP205
Excited to see this one. If you take that many pics of just the tear down would like to see how many we get with the actual detail of the build. ha Keep them coming..

ls1nova71 03-18-2015 10:53 PM

Re: 1972 Jimmy + 5.3/4L60E/NP205
Well, I guess there's no going back now! I'll be watching, and if there's anything I can do to help, just ask.

GMC-YA68 03-22-2015 01:14 AM

Re: 1972 Jimmy + 5.3/4L60E/NP205

Originally Posted by ls1nova71 (Post 7096528)
Well, I guess there's no going back now! I'll be watching, and if there's anything I can do to help, just ask.

You'll be sick of me by the time I'm done!

Update: got the engine/tranny and all the goodies Friday. Popped the valve covers and everything looks sweeeet and pretty in there! Pics coming.

GMC-YA68 03-22-2015 09:54 PM

Re: 1972 Jimmy + 5.3/4L60E/NP205
Got the engine/tranny and the good stuff picked up Friday...
Tore her down and got some paint on her today with the help from my lil girlie...

Justin@EntropyRad 03-24-2015 11:36 AM

Re: 1972 Jimmy + 5.3/4L60E/NP205
Motor looks nice and clean inside!

GMC-YA68 04-07-2015 10:26 PM

Re: 1972 Jimmy + 5.3/4L60E/NP205
Few things trickling in over the last week...
Ordered the DD gauges with the ECM interface.
Ordered the PacFab crossmember
Ordered the AA kit with all the parts. - FYI - I ordered this from Summit Racing and it was about $100 cheaper than AA. Plus free shipping. It was all in stock and was here in 2 days.

ls1nova71 05-13-2015 03:37 AM

Re: 1972 Jimmy + 5.3/4L60E/NP205
Are you ever going to update this build theead? I know youve got some things done....... :metal:

hemi43 05-13-2015 08:36 AM

Re: 1972 Jimmy + 5.3/4L60E/NP205
Yeah, I'm curious too !! I just received my adapter kit, and I'm really liking that Dakota dash cluster. Looks like one of those is in my future too.

Maddoxdb 05-13-2015 08:55 AM

Re: 1972 Jimmy + 5.3/4L60E/NP205

GMC-YA68 05-21-2015 11:41 PM

Re: 1972 Jimmy + 5.3/4L60E/NP205
alright alright... little bit of an update.

First - my original frame had been in a wreck, hacked up, and a new front end welded back on very poorly.. Both frame rails had been cut just under the firewall. The "donor" front end they found was from a 71 truck. The truck had always driven straight, but this just looked like an accident waiting to happen. So I got a SWEET deal on another 72 frame from board member larryd. I pulled the old frame out and the new frame got blasted and powder coated.

I won't be running AC so I pulled all this off and got a AC delete cover that I will be using in it's place.

Then the frame removal....

Then the new frame got back from the coater. Turned out awesome. I purchased new 2.5 lift springs front and rear from Skyjacker at this time as well. Got everything loosely bolted up and she at least rolls right now.

Also installed a 87 blazer tank (31 gallon) and the sending unit to match. I'm going to run a walbro 255 in tank in place of the factory 87 pump since it is not high pressure.

GMC-YA68 06-07-2015 10:40 PM

Re: 1972 Jimmy + 5.3/4L60E/NP205
I went to go have the local tranny shop swap out my AA output shaft and come to find out it was toast (the tranny) despite only having 55k miles on it. I called the lot I got it from and they told me that the t-case from the donor truck was cracked when they got the truck and someone must have driven it while all the fluid was leaking out and burned it up. Long story short, they are crediting me and I had another one I already had, rebuilt with some upgraded parts and shift kit. So now everything is brand new and no worries there anymore.

I installed the t-case with new poly bushings and the x-member. And then hooked up the rest of the AA kit to the back of the tranny (VSS, clocking ring, etc)

It was time to do a mock up in order to find out where my PacFab engine crossmember needed to be installed so I did that today. Got it all installed. Went pretty well. The bump stop brackets needed to be removed as the X-member was right on top of the factory rivets.

Next I am going to plumb all my fuel, transmission, brake lines while the drivetrain is on the frame. If I was smart I would have backed my truck into the garage for the tear down, I can't get the frame back under it with the engine/tranny installed so I'll pull those when the time comes and put the body back on.

hemi43 06-08-2015 08:53 AM

Re: 1972 Jimmy + 5.3/4L60E/NP205
Looking good !! You mentioned that you had the frame powder coated, but what did you use to paint the diff housings? I've been trying to find a 2-part semi gloss black and ended up buying some Eastwood product.
Also, how much more forward does the 5.3 end up as compared to the original engine?
I've been gathering parts for the past couple months and will be doing almost the exact build that you're doing.

GMC-YA68 06-08-2015 02:45 PM

Re: 1972 Jimmy + 5.3/4L60E/NP205
I just used the "semi-gloss" black in the Dupli-color Engine Enamel.

I had the axles blasted down to bare metal, so I hit them with some self-etching primer first.

I don't have the exact measurements but I would guess that it moved the engine forward around 2" or less. If you want, measure from your crank pulley on yours to the front crossmember and I'll do the same.

hemi43 06-09-2015 10:35 AM

Re: 1972 Jimmy + 5.3/4L60E/NP205
I just checked the location of the original engine, and the front of the pulley is 11 1/4" from the rad support. I would estimate that the pulley is about 2 1/4 inches away from the rear lower part of the cross member. Regardless, there's tons of room.
I'm still debating whether I'll be running AC. Do you think there's enough clearance for the l 5.3 compressor in it's original location?
I just cleaned the block on my 5.3, and looks just as clean as yours under the rocker cover. The block itself though was coated with a layer of rust about 1/16 thick thanks to our Canadian winters and road salt.
Another question I had is which power steering pump will you be using? I'd like to use the one on the 5.3, but concerned about differences in pressure.
BTW, my truck is originally from Salem Missouri.

GMC-YA68 06-10-2015 12:34 PM

Re: 1972 Jimmy + 5.3/4L60E/NP205
My crank pulley to the front crossmember is right at 1 1/4"

I slapped on my AC compressor and took some pictures. I don't think it is going to happen without notching the frame. A custom fitting wouldn't be an option either, at least from the angles I am looking at. A different mount would be the best way to do this.

As far as the power steering I am planning on using the factory 5.3 pump with a hydroboost out of the same year 04-2500. I have heard you can use a fitting on the rear of the pump to reduce the flow of the fluid. I'll post the picture and part # if I find it.

GMC-YA68 06-10-2015 09:21 PM

Re: 1972 Jimmy + 5.3/4L60E/NP205
Here is the reducer a fellow board member (shears) has used to reduced the pressure. His pump was bubbling from so much fluid flow and causing his pump to starve.

hemi43 06-11-2015 08:40 AM

Re: 1972 Jimmy + 5.3/4L60E/NP205
Thanks for the info Keegan !! Showing the location of the AC compressor answers my questions. Like I said, i'm still not sure if I'll be running AC or not, but if there's clearance issues using the OEM compressor I may just machine custom brackets and use a Sanden compressor. I'm hoping to start my build thread in a few weeks.

partsstoreguy 06-11-2015 10:48 AM

Re: 1972 Jimmy + 5.3/4L60E/NP205
I like the added capacity and the factory looks of the 80s fuel tank. Were there any problems getting it into place?

GMC-YA68 06-12-2015 01:21 PM

Re: 1972 Jimmy + 5.3/4L60E/NP205
No, the tank fit well. I placed the front crossmember on the frame to where the tank fits very snug.

Justin@EntropyRad 06-25-2015 02:49 PM

Re: 1972 Jimmy + 5.3/4L60E/NP205
Still really dig this build man. The close-up pic of your kiddo wrenching on the engine is framable

Tillik 07-11-2015 02:55 PM

Re: 1972 Jimmy + 5.3/4L60E/NP205
Very nice build. Keep it up!

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