73 J4000 from AZ

[Overland_az]

Hey y'all

Just picked up a 73 J4000 360/th400/QT.
Runs great has some dings and dents but overall not bad. Learning quickly the parts are very hard to come by for these trucks. Plan is to get it running great then slowly restore it. Looking forward to this build.

[joe]

For any parts hunt it'd be a help especially at an auto parts store if you mention which model you have. 4000 is just a wheelbase designation. From there the underneath stuff varies if J-4500, J-4600, J-4700, J-4800.
Have fun. I had a 73 J-4600 w/ 360/AT/Qt/D60-2 rear/4.09 gears. It was an excellent tough general/normal use old truck. Welcome to the affliction.

[Overland_az]

For any parts hunt it'd be a help especially at an auto parts store if you mention which model you have. 4000 is just a wheelbase designation. From there the underneath stuff varies if J-4500, J-4600, J-4700, J-4800.
Have fun. I had a 73 J-4600 w/ 360/AT/Qt/D60-2 rear/4.09 gears. It was an excellent tough general/normal use old truck. Welcome to the affliction.

Hey Joe. Thanks for the advice. How would i know which model I have? I thought 4000 was the model. Noob.

[joe]

There should be a build sticker on the driver side door jamb. It'll have the how ordered model designation. How ordered related to the GVWR ordered. A J-4500 will have a GVWR OF 5000 LBS. J4600 will be 6000 GVWR, etc. Biggest difference is mainly rear axle and related parts. J-4500 will have a D44, 4600 and 4700 D60-2 semi floater, 4800 D60 full floater. If the sticker is gone on yours the VIN decoder on this forums Tech Library will tell you GVWR. http://www.ifsja.org/tech/figures/index.html
A 73 won't likely even show up on a parts store computer so they'll have to look in their old paper vendor books and those are "model specific".

[Overland_az]

There should be a build sticker on the driver side door jamb. It'll have the how ordered model designation. How ordered related to the GVWR ordered. A J-4500 will have a GVWR OF 5000 LBS. J4600 will be 6000 GVWR, etc. Biggest difference is mainly rear axle and related parts. J-4500 will have a D44, 4600 and 4700 D60-2 semi floater, 4800 D60 full floater. If the sticker is gone on yours the VIN decoder on this forums Tech Library will tell you GVWR.[/IMG]ex.html[/url]
A 73 won't likely even show up on a parts store computer so they'll have to look in their old paper vendor books and those are "model specific".

Gotcha. The Id tag on the door jamb says GVWR of 6000 but the decal on the driver side front fender says GVW 8000. I Know The rear is a dana 60 and according to the ID tag it has 4.10 gears, don't Know if it's a semi or full float. Also it looks as if the gas tank was relocated inside the cab behind the seats. P.O said it had dual tanks at one point maybe I have Frankenstein model haha

[joe]

Gotcha. The Id tag on the door jamb says GVWR of 6000 but the decal on the driver side front fender says GVW 8000. I Know The rear is a dana 60 and according to the ID tag it has 4.10 gears, don't Know if it's a semi or full float. Also it looks as if the gas tank was relocated inside the cab behind the seats. P.O said it had dual tanks at one point maybe I have Frankenstein model haha

Never seen or even heard of a factory 8000 GVWR fender sticker. That's an owner stick-on. If the factory door jamb sticker and VIN say J-4600(6000 GVWR) it came from the factory with a D60-2 semi-floater. Easiest way to tel is: the full floater D60 will have the hub sticking out through the wheel center a few inches(3?) On the semi-floater the wheel mounts flush to the drum. Also pretty sure even in 73 the D60 full floaters ran 8 lug wheels compared to the D44 and D60-2 semi-floaters with 5 lug rims.
You may well have a frankenjeep. NOT uncommon that a 45 year old FS Jeep has been modified over the years with who knows what door parts. The trimmed fender flares are an obvious clue.
Depending on your end game plan good looking start. Have fun.

[Overland_az]

Never seen or even heard of a factory 8000 GVWR fender sticker. That's an owner stick-on. If the factory door jamb sticker and VIN say J-4600(6000 GVWR) it came from the factory with a D60-2 semi-floater. Easiest way to tel is: the full floater D60 will have the hub sticking out through the wheel center a few inches(3?) On the semi-floater the wheel mounts flush to the drum. Also pretty sure even in 73 the D60 full floaters ran 8 lug wheels compared to the D44 and D60-2 semi-floaters with 5 lug rims.
You may well have a frankenjeep. NOT uncommon that a 45 year old FS Jeep has been modified over the years with who knows what door parts. The trimmed fender flares are an obvious clue.
Depending on your end game plan good looking start. Have fun.

I'm gonna go with what the vin says. I have center caps that stick out pretty far so I can't tell what's behind it until I take the tire off, then I'll know what I'm dealing with. Either way it's gonna be a fun build. I'll start a build thread once I actually start working on it. I have a 96 xj that needs some loving first. I did find a lever on a the driver side floor that looks like it controlled what tank you were using. Pretty cool! I might end up making it a dual tank down the road. Thanks for the help Joe!

[joe]

Though never seeing one in person Ive heard and read of behind the seat aux tanks in some eras of J-trucks. No idea what they used for switching to-from aux tanks and gauges but if old school mechanical switch valve, I would expect it to be on the floor between the drivers seat and thedoor. If electrical switch valve I'd expect the switch to be on the dash. The lever you mention on the drivers side of the trans tunnel right in front of the seat is likely the High/Low range shifter for the QT tcase. The normal 4WD/E-drive vacuum selector switch is in the glove box or maybe on the dash? Mine was on the dash near the steering column Wasn't stock/original but made sense even to the PO.

[Overland_az]

Though never seeing one in person Ive heard and read of behind the seat aux tanks in some eras of J-trucks. No idea what they used for switching to-from aux tanks and gauges but if old school mechanical switch valve, I would expect it to be on the floor between the drivers seat and thedoor. If electrical switch valve I'd expect the switch to be on the dash. The lever you mention on the drivers side of the trans tunnel right in front of the seat is likely the High/Low range shifter for the QT tcase. The normal 4WD/E-drive vacuum selector switch is in the glove box or maybe on the dash? Mine was on the dash near the steering column Wasn't stock/original but made sense even to the PO.

The switch I'm talking about is on the driver side floor by the door I looked under the jeep and it goes to a t style hose connector that is no longer connected to anything but the fuel lines run passed it. There was a lever on the dash labeled low range but I haven't messed with it too much.

[mud89]

Gotcha. The Id tag on the door jamb says GVWR of 6000 but the decal on the driver side front fender says GVW 8000.

It's strange ?
A 73 has a yellow decal on the door jamb with VIN , GVWR and the production date, and an ID metal plate on the firewall, driver side, with VIN, paint and trim codes. I don't know what you mean by a decal on the front fender ?

[joe]

It's strange ?
A 73 has a yellow decal on the door jamb with VIN , GVWR and the production date, and an ID metal plate on the firewall, driver side, with VIN, paint and trim codes. I don't know what you mean by a decal on the front fender ?

Yeah that is strange. Back in the 70's in WA we (the company) had to have the GVWR rating (2" numbers) displayed on both sides of the company trucks. Always thought it was a new WA thing but we were the NW exploration div of an AZ based mining co. Our 4x4's were plated in WA but the titles/ownership were AZ papered. Maybe it was an AZ thing back then? It ain't factory.

[mud89]

In my country ,commercial vehicles or trucks have a sticker on the body side with GVW and dimensions

[Overland_az]

Heres the yellow ID tag in the door jamb



And heres the decal on the drivers side fender



and last but not least the aux gas tank behind the seats.

[mud89]

Thanks for sharing, yellow sticker looks original, the 8000 GVW sticker is not from factory. Seems that you don't have the ID plate on the firewall ? Could be lost (BTW 73 is the first year for this plate on the FW)

[Overland_az]

Thanks for sharing, yellow sticker looks original, the 8000 GVW sticker is not from factory. Seems that you don't have the ID plate on the firewall ? Could be lost (BTW 73 is the first year for this plate on the FW)

I'll take a look later today for ID plate on the firewall. Do you guys know if the dash is interchangeable throughout the j series truck? Mine is cracked and brittle.