Builds 1970 FatherSonJ40 project

[Kmehr]

Does anyone know if I can swap the larger pattern flange yoke onto my 3spd driveshaft? I.e. are the joints the same? There is surprisingly little info out here on this!

37315-2, 4 SPEED DRIVESHAFT FLANGE YOKE

37315-2, DRIVESHAFT FLANGE YOKE. 4 SPEED 1974-8407. ORDER HERE Fits 4 speed driveshafts, front or rear or either drive shaft, front or rear. 1974-8407 bolt pattern. Does not fit 8408 and later. These models have a different bolt pattern.

tpi4x4.com

 

[pb4ugo]

You can interchange yoke ends because the slip joint splines are the same. You can swap pinion flanges too. They are either coarse or fine spline flanges. Some pinions have crush sleeves, so you need to know what you're desling with. @cruiseroutfit can help you out. You can get a round flange and drill it.

 

[pb4ugo]

I think the joints are different.

 

[Kmehr]

I think the joints are different.

Looks like they changed in 74. Bummer.

My driveshaft tube has a big dent in it, so might just be time. Wanted to wait till I got the new power train in to get a custom driveshaft…

 

[Kmehr]

Getting close to having the axle all ready to rip. Ended up just drilling the round pinion flange to match my existing driveshaft. It took forever, but was the free option. Just couldn’t justify a few hundred on a new shaft when the plan is 12HT soonish which will require a new one anyways.

Made a little bracket to hold the cable pull. Also had to wait on new axle side shock studs since a PO welded them to my old axle.

Also finished up my front bumper. Welded in some beefy D rings to mount my brand new tow bar. Painted it with steel-it, so my obsession with that stuff continues. Went with an NSA tow bar with a mechanical brake system. Very pricey, but actually much cheaper than an electronic brake setup alone from a lot of the big names. Haven’t tried installing it yet, but it looks very well made.

The final two pieces to my flat tow dreams are a full soft top, which I ordered through Ian here on mud. The last is new wheels. I know many have been running the 10.5 on the stock wheels like I am, but being 2.5in wider than the approved rim width just doesn’t scream safety to me, especially Since I plan to tow at interstate speeds in the future. I’ve been waiting patiently for the new Nomad 504 fields in white, with the hub caps. They look awesome and very stockish, and have so many more tire options. Looking at the new Falken AT4Ws in 255/85r16. I have the AT3Ws on my truck and like them a lot.

Oh and I need to weld together my metal tech cage. Surely I’m close to being done with the “big ticket items”….

Got a father son camping trip in this weekend. They boys had so much fun, so really itching to tow the 40 next time and be able to explore all of the trails!

 

[Kmehr]

Axle is in and tested. Everything is working as it should! Took it for a spin and all is well.

 

[Kmehr]

New rubber arrived today. Still waiting on wheels that look like late June, but wanted to scoop tires before tariffs and the expected price hike happened May 1. Man I’m glad I went ahead and bought as they went up $25/tire overnight May 1!

Picked the Falken wildpeak AT4W in 255/85r16. Waiting on the Nomad 504 fields in vintage white 16x7. My BFGs are almost new as far as tread life, but they’re all 10 years old and are starting to show some sidewall cracks. Plus, I know tons of people do and have done it, but the whole 10.5 tire on a 5in wide rim just really doesn’t feel like the safest combo!

 

[Kmehr]

Question for the experts- I swapped over all of my disc brake parts from my old axle to my new axle, everything "fit" just fine. I noticed a grinding noise from the rear wheels, particularly on turns to that side. I feel no axial play at the hub if I try and jiggle it, and the wheel free spins with about the same amount of resistance as the front wheels, with no brakes, so I really don't think its wheel/hub bearings.

Upon closer inspection, on my new axle, the distance between the rotor mounting surface and the caliper mounting surface is 5/32 greater on my new axle than my old axle. Is this significant enough I need to make a change? Or is it an amount that the caliper can adjust for? With the brakes installed, there is certainly more free spin resistance on the rear wheels than the front. I guess I'm unsure if the movement is limited to the piston extending and retracting, or if the whole caliper slide along the "pin". As you can see, in the old setup, there is some distance between the head of the pin, and the body of the caliper, but not the case on the new axle.

Here are some photos of the red (old axle) and black (new axle) for comparison:

 

[pb4ugo]

It appears the metal backing part of the outer pad is contacting the rotor hat. It's already worn a groove in the hat. You can remove the brake pad and grind the metal edge on the pad for more clearance.

 

[pb4ugo]

 

[Kmehr]

New pads appear to have solved the grinding noise. Rear wheels are still harder to free spin than the front, or at least were before I went for a test drive. The truck still rolls in neutral, so I think I’m chalking this one up to being ok.

Really need to switch gears for a bit and get my Alfa running again, but I’m dying to get my cage welded up and keep rolling on things with this. It’s so fun!

 

[Kmehr]

Had some fun with my youngest today, unreal these trails are only about 10min from my house.

The locker really works well and we were able to crawl right up this little hill. Definitely can see where lower low range would be nice.

Still have some grinding noise coming from the right side when warm that goes away at the slightest touch of the brakes. Maybe the front right needs some work or my rear rotor is glazed. More investigation needed.

After a couple unintentionally hard launches in low range, 3 out of 4 bolts holding my driveshaft to the rear pinion flange left the building. Thought my transfer case had exploded or something. Was able to pull it and drive home in front wheel drive.

 

[Kmehr]

Question for the experts that I really can’t find an answer to- I have a diaphragm style clutch brand new in the box. My current clutch is the 3 finger clutch. Can I reuse my flywheel if I swap clutch styles? It’s due. Making a good debut iOf chatter and my throw out bearing is squealing. It’d be great if I could use the clutch I have just sitting on the shelf and already paid for….

 

[charliemeyer007]

I don't think so. Sell your disk and buy the correct one.

 

[Kmehr]

Of course my Alfa is still sitting collecting dust, but I have made some progress on the new cage. The big stuff is tack welded in place. Tried to use my ancient drill press as a hole saw notched and it’s so far out of true now it’s worthless. Ended up free handing most of it with the grinder. Wasn’t as intimidating as I initially thought but defiantly have some gaps to fill… the “out of time” pieces are up next and I’m not really sure how to template those out.

TROA top is here waiting on the cage to be done to get installed next.

 

[Kmehr]

Getting closer to having the whole cage tacked in. These multi-plane on a bend pieces are super tricky. I really can’t figure out how to put the front angular supports in that makes them not a serious head knocker in inside to side situation. I can and want to lower the driver seat a bit, and I think that will help a lot, but I just know there will be serious forces in a rollover or crash that are unlikely to be replicated by just sitting in it.

 

[Kmehr]

FINALLY my nomad wheels arrived. Went with grey over the vintage white at the last minute. Hopefully will get them back from the tire shop tomorrow with the new rubber mounted. They appear to fit great, and clear the hubs. Ordered some extended tip lugs nuts as the mounting surface is quite a bit thicker than the steelies. Hope that works cause I really don’t want to have to disassemble all the hubs and press new ones in. Fingers crossed.

 

[Kmehr]

Waiting on the extended lug nuts to mount them all, but they’re back from the tire shop and I’m thrilled with them. These Falkens are about 1/2 narrower than the BFGs in real life measure about an inch taller.

 

[fireflyr]

Question for the experts- I swapped over all of my disc brake parts from my old axle to my new axle, everything "fit" just fine. I noticed a grinding noise from the rear wheels, particularly on turns to that side. I feel no axial play at the hub if I try and jiggle it, and the wheel free spins with about the same amount of resistance as the front wheels, with no brakes, so I really don't think its wheel/hub bearings.

Upon closer inspection, on my new axle, the distance between the rotor mounting surface and the caliper mounting surface is 5/32 greater on my new axle than my old axle. Is this significant enough I need to make a change? Or is it an amount that the caliper can adjust for? With the brakes installed, there is certainly more free spin resistance on the rear wheels than the front. I guess I'm unsure if the movement is limited to the piston extending and retracting, or if the whole caliper slide along the "pin". As you can see, in the old setup, there is some distance between the head of the pin, and the body of the caliper, but not the case on the new axle.

Here are some photos of the red (old axle) and black (new axle) for comparison:

View attachment 3901764

View attachment 3901765

View attachment 3901766

View attachment 3901767

My brakes were doing the same thing. A brake guy showed me how to bend these tabs down with a punch and hammer to make the pads ride higher.

 

[pb4ugo]

That's the proper way.