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Intermediate Frankenjeep Build

Jon B.

Retired three times; still working.
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Joined
Apr 6, 2022
I guess this is the time and place to put a build thread…

The project: A 1972-1975 group of parts into a single off- and on-road capable CJ5.

It will have: A 1975 frame (purchased from @C-dubb here), an aluminum block LS 5.3 from an ‘05 GMC Envoy, an SM465 four-speed from a ‘91 Chevy one-ton service truck, a Dana 20 transfer case from either the ‘72 or the ‘74 donor Jeep, axles & suspension from a roller frame I found on Craigslist, a tub from the book of faces market place - Colorado Springs, and miscellaneous parts off the ‘72 donor. I haven’t yet decided whether to use the ‘72 or the ‘74 VIN to title it. The ‘74 has a factory data plate; the ‘72 appears to be homemade.
Gotta find seats and such but that’s way down the road.
Here are some teaser pics:
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Hmmm… I thought I had a pic of the donor tub. Guess not.

The engine has a new cam, lifters, valve springs and seals, oil pump, gaskets and such. Probably more, but I forget.
Transmission will get some goodness from Novak, as well as an adapter to the D20.

The frame is fully boxed, cleaned & painted, and ready for the rest. Springs and shocks are Skyjacker, with a 3-4” lift. Axles are a D44 rear and D30 front; 11” drums all around. They have 4.27:1 gears, and will have (probably) Eaton Truetrac limited slip differentials in both.

The front axle came apart today. It’s not good…Rusty bearings, and one spindle is boogered. I have four others on the two donors, though. I’ll likely order the Eaton and a rebuild kit from Summit, along with some misc. stuff. I told Mrs. B. that I’m at the point where it’s more money than labor for a while…

Jon B.
 
I boxed the frame last week.

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A local fab and steel shop sheared some 10 ga. plate at 4-1/4” by 48” long which worked well.
There was a lot of CAD involved; many pieces of cardboard were drawn and cut.

The bad paint job sorta hides my bad MIG welding job. I can’t blame the equipment: an ESAB 250 unit, belonging to my brother.

Since I know there’s gonna be more drilling, cutting and welding involved, I primed and painted it with Rustoleum rattle cans. I’m 69 years old; the frame will be fine after I’m dead and gone. :)

More later; thanks for reading!

Jon B.
 
I'm glad to hear your frame will be fully boxed.
Since your engine usually makes HP & torque at higher RPM...your gear ratio of 4:27 should be good. Anything lower creates a weaker pinion to ring gear engagement.
Are those 31 or 33" tires?
I'm following closely as there's much more support for intermediates these days.
And I hope to see you in Silverton for the September trip!
 
I'm glad to hear your frame will be fully boxed.
Since your engine usually makes HP & torque at higher RPM...your gear ratio of 4:27 should be good. Anything lower creates a weaker pinion to ring gear engagement.
Are those 31 or 33" tires?
I'm following closely as there's much more support for intermediates these days.
And I hope to see you in Silverton for the September trip!

The cam I bought & installed is a “Truck Norris” from BTR. The objective was torque from idle to 3500 RPM. Time will tell it it gets met. It should still review high enough to get 65-70 mph on the highway.

Those tires are Mickey Thompson 33x12.5-15 on American Racing wheels (10”??).

Still hoping (too early for actually planning) on the Colorado trip, but with the ‘68.

Jon B.
 
The cam I bought & installed is a “Truck Norris” from BTR. The objective was torque from idle to 3500 RPM. Time will tell if it gets met. It should still review high enough to get 65-70 mph on the highway.
Those tires are Mickey Thompson 33x12.5-15 on American Racing wheels (10”??).
Still hoping (too early for actually planning) on the Colorado trip, but with the ‘68.

Jon B.
Good choice with the cam! 33s should be a good match with your engine and axle ratio...of course it sounds like you have this figured out already!
10-4 on Silverton.
 
The 5.3 came off a Craigslist ad, by La Crosse, Wisconsin. It allegedly has 170k on it but…

The cylinders still have the honing marks, the rod bearings are great, and it was remarkably clean inside. The DOD/AFM left a lot of oil soot, as that tends to cause oil burning. That’s been omitted with the new cam & lifters.

The original oil pan was a front sump, and the Envoy front differential bolted to it! One axle actually went through the pan to the opposite wheel. I bought a bad Silverado 5.3 and grabbed the pan, windage tray, oil pickup and dipstick off it. It’s been a source of misc. fasteners, as well.

I have to take the PCM to a local (50 miles away) speed shop for reprogramming before that goes on.
Gonna keep the drive-by-wire throttle and the first set of O2 sensors for the fuel injection.

I’m hoping that the tall intake manifold fits under the hood. We’ll see.

Jon B.
 
Oh, yeah…

Before I tore the engine down, I borrowed a set of gauges and did a leak-down test. None of the cylinders were over 10% leakage and five of them were 5-8%. At 20, it’s a concern, and at 30, you’ve got serious problems. I was pleased!

I did have to buy a book to learn how to work on the Gen 3-4 engines. I’ve overhauled an odd-fire 225, an AMC 304, and Chevy small and big blocks but the LS series is a whole ‘nuther thing. Needed some new tools, too: angle gauge for torquing bolts, a valve spring compressor. Aligning front & rear covers and the oil pan are a new experience, also.

I found the SM465 on Craigslist, about 100 miles from home. $200 bought the tranny, bell housing, (350) flywheel, clutch plate and a decent clutch disc. Only the bell housing is of use, now. Gotta get a bunch of stuff from Novak to mate the 465 to the LS.

Jon B.
 
Ouch!
A big order sent to Novak. $1600+!
Flywheel & pilot bushing
Gaskets & goodies for the 465
Adapter to the D20
Mount for adapter
Other stuff I can’t think of right now

That’s in addition to the $800+ at Summit, Jeepsterman and Vevor (bearing puller).

It’s a good thing I got a $1500 year-end bonus from my employer today.

Any tips on driving inner oil seals in the D30 housing are welcome. And inner spindle bearings. Never done that before - or set clearances for a differential for that matter.

Jon B.
 
These work fine for pulling seals, but you can usually wiggle a screwdriver behind the seal and do the same.
Amazon.com: Lisle 56750 Seal Puller , black : Automotive

There should be clearance cut(s) in your hub that will allow a punch to drive out the bearing races from the opposite side.

Check YouTube for backlash and gear contact pattern engagement guidance. Remember, the front is not as critical as the rear, simply because it's not engaged as much of the time. Close is 'good enough'.
 
Today was the first of many, I presume, delays…

The rust on the ring gear is worse that I initially thought. So, after much internal debate, I gave in and ordered a new set from Summit. :-(

Out of stock but the manufacturer/distributor will drop-ship when it’s available.

I did get the new Truetrac and install kit but it’s gonna sit on the shelf for a while. The inner seals are in the housing! That was no fun. The first (well, second, since I ruined the first one) took about 2-1/2 hours - fabricating driver, etc. In the end, I started it with the reshaped timing sprocket off the 5.3 crankshaft and finished with a three-foot piece of 1/2” black iron pipe. Second one took 6 minutes, more or less.

The Novak stuff may be here soon, so I can start working on the 465 transmission and D20 transfer case. All is not lost.

One of the boilers at our church failed, fatally; new one required. Contractor says $43k installed! My year-end bonus will likely be donated for that, so the Novak funds will get dug out of the bank account.

Jon B.
 
Power disk brakes up front and ditch those drums. Rear drums if they have integral E brakes are perfect. This is gonna be cool.

Nah. Gonna stay with drums. Here’s why:

A while ago, I asked about swapping out the 10” drums on my ‘68 CJ5 for 11” drums. The opinions here were “Don’t bother, just tune up the originals and they’ll do nicely “. I agree.

If I was going with 37 or 40” tires, then, yes, big discs for sure.

Jon B.
 
Nah. Gonna stay with drums. Here’s why:

A while ago, I asked about swapping out the 10” drums on my ‘68 CJ5 for 11” drums. The opinions here were “Don’t bother, just tune up the originals and they’ll do nicely “. I agree.

If I was going with 37 or 40” tires, then, yes, big discs for sure.

Jon B.
Apples to oranges. If you already have 10" drums and you were asking about 11". then why bother? Now if you were asking about lockheed style heel toe 9" or bendix style 11", then 11".. But even then, why? The disk stuff is everywhere, bolts on to D25/27/30, is cheaper than the drums and if you're going big engine, why stay with antique brakes when more modern is so simple and cheaper? Big engine and hard to stop is not something I want on get in front of.

And I am on here too, done a good bit of projects and builds over the years. So this is my experience and not opinion from a safety standpoint.
 
You guys are certainly eager to spend my money! :-)

Il have at least $1k just in this front axle as it is. The money well isn’t bottomless, you know.

Maybe down the road, I’ll re-examine the front brake issue but as of now, I’m sticking with the existing drums.
The engine is “big” but isn’t any heavier than the 304 in the ‘72. More potent? Surely! But not heavier. This thing won’t be screaming along at 100mph. I’m thinking all will be well. If not, you can say “I told you so!”
 
You guys are certainly eager to spend my money! :)

Il have at least $1k just in this front axle as it is. The money well isn’t bottomless, you know.

Maybe down the road, I’ll re-examine the front brake issue but as of now, I’m sticking with the existing drums.
The engine is “big” but isn’t any heavier than the 304 in the ‘72. More potent? Surely! But not heavier. This thing won’t be screaming along at 100mph. I’m thinking all will be well. If not, you can say “I told you so!”
s

There are two major advantages to disk brakes over drums:
  1. Disks work when they are wet. The pads shed the water off the disk immediately and begin to brake. Drums hold water inside and do not shed it. You literally have no brakes for quite a while with drums after a river crossing. In the old days you could et "Velva-touch" shoe linings to combat this, but that sort of stuff isn't available anymore.
  2. Less of a concern with an old light Jeep, but disks cool much better. Drums stopping from high speeds, or controlling speed down long grades simply can not compete with disk brakes for heat rejection.
Both of those are big deals. Drums do however have one advantage over the same diameter disks that dual leading shoe drums are self-enrgizing and tend to provide more brake force for a given hydraulic pressure. However, this advantage is generally overridden by the above and a power booster if needed.
 
You can always do the brake upgrade after the rest of the axle is installed. You can get any bugs worked out with the engine transplant.
Is your existing drum hardware suitable for short-term use?
...just trying to save a few of your dollars now...but please keep this highly recommended upgrade in mind.
 
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