72 FJ40 project info needed. (1 Viewer)

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

Joined
Oct 8, 2021
Threads
1
Messages
5
Location
Gardena, California
Hello all,

I'm working on my cousin's 72 FJ40 that he recently got in trade for some work he did. It's in good condition and has many upgrades. Someone has installed a fuel injected small block Chevy, aluminum radiator with electric fan, AutoMeter gauges, Painless wiring harness, a lift, rims and tires, 12k winch, front bumper, rear spare tire and cooler mount, aftermarket fuel tank with skid plate, multiple toggle switches, and 4 wheel disc brakes. My cousin is giving this to his wife, but she doesn't know how to drive a manual trans. So he wants to install an automatic. I was looking at installing a 700R4, 4L60, or 4L60E trans. Then using an Advanced Adapters kit to mate it to the transfer case. There are several options from AA to choose from based on what transfer case you have (ie: 10, 16, 19 spline). Is there a way to identify what transfer case is in this FJ? Or do I have to remove it first to count the splines? Just trying to see if I can acquire the parts before tearing this thing apart. Also, I'm guessing that this swap is not just an easy job of just installing the new trans and adapter and a shifter. I know I have to buy or make a new transmission crossmember. Will I have to lengthen or shorten the drive shafts? Do I need to modify the transfer case linkage to keep the T-case shifter in the stock location? I'm new to the FJ world, but I'm fully capable of doing any modifications or fabrication that needs to be done. Just looking for some help in figuring out the identity of the T-case and any knowledge or experience in doing a swap like this.

Also, the manual trans in this FJ has L, 1, 2, 3, OD, and R on the shift knob. Is this a 5spd? Or 4spd with granny gear? I believe that the trans and T-case are stock, but not sure. The productions date on this FJ is 11/71.
 
Is it actually a 5 speed? You probably need to id the trans to help determine what t/case it has. You can probably remove the cone on the back of the t/case and count the splines, if in fact it still has a 40 case. 72 would have had a 3 speed. Lets see some pics. An auto setup can be long driveline, so is the 5 speed setup.
 
Here are a few pics of the trans and T-case. I didn't see any placard with model or serial numbers for identification.
IMG_20210926_183458458.jpg
IMG_20210926_183552380.jpg
IMG_20210926_183614002.jpg
IMG_20210926_183624310.jpg
IMG_20210926_183633129.jpg
 
My suggestion is keep the manual trans and teach the wife how to drive a manual trans. First, it won't cost any money; second, an auto trans will likely add additional length that will make fitment problematic.

As to existing trans, could be an NV4500 5 speed. First is a granny low, second is normally used as a first gear, third and forth would be like any of the last two gears in a 3 or 4 speed and 5th is over drive.
 
Last edited:
Thank you Byron for the information. I'm taking it to work tomorrow to pressure wash the undercarriage so it's cleaner and not so greasy. Then I'll be removing the trans and T-case. And I'll see if there's some numbers for me to identify what this thing has. I'll also take some more pics of them.
 
Sure looks like an NV4500. The easiest way to tell will probably be to pull the numbers from that AA adapter. Should tell you just about everything. There aren't many possibilities, either Dodge or GM, and a few year differences. I love both my NVs, I'd highly recommend keeping it.
 
After pressure washing the undercarriage of the FJ40, I was able to see the numbers on everything. The trans numbers show that it's NV4500. I believe an early GM model. The AA adapter is used on both the GM and Dodge transmissions. I haven't searched the numbers on the T-case yet, but I'm pretty sure it's stock. The pattern matches the pattern on the placard mounted on the glove box door. Thank you guys very much for the help in finding/researching this information. If anyone needs or knows someone that needs/wants an NV4500 trans with clutch, and AA adapter, I'll have one for sale soon. I have the clutch master, line, and slave to go with it.
 
really, manual isn't hard to learn - and she will earn lots of admiration for being able to drive one

FJ40s are total dude magnets :D - so much potential in case the current domestic arrangement goes sour :flipoff2:
 
Its your 40, so do what you want. Its a 40 t/case. All 40 t/cases have the same shifting pattern. If you go to faq's at the top of this section then go to tech links, scroll down and you'll find a link to a 4 wheel and off road article which may help in id'ing the case. I think you'll have to dive deeper into the case to determine which one you have. As for learning to drive a stick, thats between you and your significant other. Seeing it has high and low range it becomes easier to learn shifting while in low range, if she wants to.
If you go auto, be sure you have good brakes and keeping it cool could be challenging. Its been done b4. That 5 speed setup should sell quickly. Do your research, on auto/tcase choices.
 
Last edited:
Thank you for the information. I'll try to find that article to help me identify the T-case. I'm definitely learning a lot about FJ's doing this project. I agree about learning to drive stick. I learned to drive in a manual and I taught my son to drive in a manual. This FJ is my cousin's vehicle and his wife has no desire to learn stick. I've tried to sway them to teach her, but wasn't successful.
 
Thank you for the information. I'll try to find that article to help me identify the T-case. I'm definitely learning a lot about FJ's doing this project. I agree about learning to drive stick. I learned to drive in a manual and I taught my son to drive in a manual. This FJ is my cousin's vehicle and his wife has no desire to learn stick. I've tried to sway them to teach her, but wasn't successful.

This thread may have some pertinent info.

 
Thank you for the information. I'll try to find that article to help me identify the T-case. I'm definitely learning a lot about FJ's doing this project. I agree about learning to drive stick. I learned to drive in a manual and I taught my son to drive in a manual. This FJ is my cousin's vehicle and his wife has no desire to learn stick. I've tried to sway them to teach her, but wasn't successful.
Post #10 in the link above that @DangerNoodle referenced is the article. The top pic in the article is my 40 on a 1st place run on the obstacle course at the 4 Wheel & Off Road Jamboree at Indianapolis. Shortly after that it got a new tub.
 
Last edited:

Users who are viewing this thread

Back
Top Bottom