Build Stretched 1-Ton FJ40

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Ditcherman said:
Been poking around as I have time and thinking about your mount.
What do you think the advantage of the Busted Knuckle mount would be, after you already have the WOD? They look similar to me from their videos, just BK welding their amount on first then machining the bearing race area, but as far as mounting goes I don't see much difference.
In watching some vid's it occurred to me that I'm solving my problems with a straight-off-the-transfer case shaft. No angles, just forward projection of the joint. If there is 1. some angle and 2. a slip joint involved, the slip would absorb the engine torque.

All that to ask if you have any angle involved, and if you have a slip joint involved? If so, mount away. (In my opinion, which may be exactly worth what you are paying for it!)

Assuming it does need to flex, can you modify the WOD mount plate and your frame to allow for those poly bushings?
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I do have some pretty funky angles going on and somewhere in this thread I posted a picture. I don’t have enough material to put a recessed bushing but I can use a flat bushing.

The Busted Knuckle mount seems stronger but you are probably right and they are most likely going to be similar in strength. This is on back order anyway so that solves that decision. I’ll move forward with the WOD mount and see what I can figure out.
 
Here is the picture, @Ditcherman. I don’t have opposing angles on the front driveline and the middle driveline doesn’t have a high angle joint and the angle at the transfercase is too steep. I am going to try raising my carrier bearing this weekend to see if that fixes the problem. I will also extend this shaft a bit so that my front shaft isn’t over extended.

 
Mike Shull said:
Here is the picture, @Ditcherman. I don’t have opposing angles on the front driveline and the middle driveline doesn’t have a high angle joint and the angle at the transfercase is too steep. I am going to try raising my carrier bearing this weekend to see if that fixes the problem. I will also extend this shaft a bit so that my front shaft isn’t over extended.

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Also post 245 page 13.
Yea I’m weird like that.
IMG_9131.jpeg


ETA if you end up raising it you could set the mount back to allow room for the poly bushings.
 
Ditcherman said:
Also post 245 page 13.
Yea I’m weird like that.
View attachment 3822410

ETA if you end up raising it you could set the mount back to allow room for the poly bushings.
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Ha! Apparently this had been a recurring topic and you can see in the picture where I went wrong by using the bungee cord to simulate angles.
 
Looking at the diagram, is it correct to say that if you move the mount so the t case 17 moves to zero, does that move the carrier angle from - I'll call it negative - seven, to a plus 10? and then does that add 10 to the already 20 diff angle?
Doesn't seem optimum but might be better, at least your angles are opposing, not with each other. Driveshafts do funny things.

ETA also can you move the carrier inboard at all? Some have made a point that the side angle is a really big deal, compounding the suspension angles.
 
My scribbles in the diagram are a bit messy. The diff angle is actually 2°, not 20.

My transfer case sits at a 3-4° downward angle towards the rear, meaning that I would have to climb upwards from the centerline of the vehicle in the front to maintain 0° at the front transfer case flange. I do not have the space to do this as the floor and exhaust are in the way, and possibly the starter, too.

The best that I can do without rotating the transfer case downward is probably 7 to 8° downward angle at the front transfer case flange. I realize that Tom Woods and other driveline/off road websites recommend to keep the first shaft as straight as possible, but Shawn Woods even recommended sacrificing those angles a bit to see if I can find a middle ground to eliminate the majority of my vibration.

I am willing to experiment with raising the carrier bearing up a bit to see if I can alleviate the angles enough to get the shaft to spin at 50 mph without any vibration. I will just tack weld the mount in a few different configurations to see what happens. If it doesn’t work then I will start tearing it apart so that I can get the transfer case off and reposition it.

@Ditcherman
 
So on my race car, I have something similar. The angles are similar, maybe worse. HAD built my set up. I have all Neapco parts as they have more angle.

1350 CV at t-case
HAD carrier bearing mounted solid to frame
1410 single u-joint
1410 Single u-joint.

I get a really steep angle at full droop at the pinion, but have never had a problem. Except when the upper link mount pulled out the frame and the front axle rotated forward and destroyed a whole bunch of stuff in a split second. It had been like that for 10 years now. Racing, rec wheeling, even mall crawling. It has been fine. :)
 
matzell said:
So on my race car, I have something similar. The angles are similar, maybe worse. HAD built my set up. I have all Neapco parts as they have more angle.

1350 CV at t-case
HAD carrier bearing mounted solid to frame
1410 single u-joint
1410 Single u-joint.

I get a really steep angle at full droop at the pinion, but have never had a problem. Except when the upper link mount pulled out the frame and the front axle rotated forward and destroyed a whole bunch of stuff in a split second. It had been like that for 10 years now. Racing, rec wheeling, even mall crawling. It has been fine. :)
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Yeah, though I get the feeling that you live on the edge more than me. Ha

I have a feeling that a few minor tweaks to my setup will fix the problem. I need to lengthen one of my front shafts anyway so plan B will probably be to experiment with Neapco joints.


Zukrider said:
Our local Ace has shoulder bolts that would work for this dilemma. No need for a sleeve. Like these.

View attachment 3822884
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This is good to know. Thanks!
 
You need to use the Neapco yokes. I had a local shop rebuild the shaft once, he used Spicer stuff. It was maxed out and would not bolt in. I had to grind the snot out of it to make it work.

My FJ40 is a lot more tame than my race car....
 
matzell said:
You need to use the Neapco yokes. I had a local shop rebuild the shaft once, he used Spicer stuff. It was maxed out and would not bolt in. I had to grind the snot out of it to make it work.

My FJ40 is a lot more tame than my race car....
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That’s good to know. Thanks for the info. My Spicer joints aren’t great. They don’t flex very far at all though they have self-cleared so the binding noise went away. It sounded like an engine getting ready to throw a rod. I’ll be happy once the vibration is tamed.
 
Mike Shull said:
@matzell, remind me again, is your engine and transmission also hard-mounted on your race car?
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It has poly bushings like above for the engine, and has a tranny mount similar and one more at the back of the 205 case. I broke two trans cases in my old car with dual cases and no rear support. 2nd case broke with a single mount that held both t-cases. I switched it up in the new car but only have one case, as it is ment to go fast... if you are crawling, you aint winning, same goes for winching!
 
The front driveline angles are good and I am moving forward with other items. The best that I could do with the angle at the transfer case is 13 1/2°, and this puts my front driveline at opposing angles of 3.5° each. There’s a slight vibration on deceleration, but it’s very minor and I bet it’s from a partially damaged ujoint from being over flexed and binding. There’s also a slight vibration at about 45 mph in four-wheel-drive but I was able to go up to 55 and it seemed fine.

This thing is a tank and these tires are amazing in the snow. I was able to drive straight up over an 8 foot snowbank. I’ll have to get pictures next time. You’ll just have to take my word for it. It was steep and the front end felt very stable and planted.

I will put a picture of where my body seams cracked when I went over that drift. I had the suspension completely flexed. I’m not sure why the body flexes that much there but I’m not going to worry about it.

IMG_2236.jpeg


IMG_2235.jpeg


image.jpg
 
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Mike Shull said:
The front driveline angles are good and I am moving forward with other items. The best that I could do with the angle at the transfer case is 13 1/2°, and this puts my front drive line at opposing angles of 3.5° each. There’s a slight vibration on deceleration, but it’s very minor and I bet it’s from a partially damaged ujoint from being over flexed and binding. There’s also a slight vibration at about 45 mph in four-wheel-drive but I was able to go up to 55 and it seemed fine.

This thing is a tank and these tires are amazing in the snow. I was able to drive straight up over an 8 foot snowbank. I’ll have to get pictures next time. You’ll just have to take my word for it. It was steep and the front end felt very stable and planted.

I will put a picture of where my body seams cracked when I went over that drift. I had the suspension completely flexed. I’m not sure why the body flexes that much there but I’m not going to worry about it.

View attachment 3824397

View attachment 3824398

View attachment 3824400
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Sounds like great improvement, and you got it done in good time too!
 
Ditcherman said:
Sounds like great improvement, and you got it done in good time too!
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No doubt! I do have some work left to put it back together, but I should be on track to take it to a trail by late spring.

I am having my intermediate shaft lengthened and balanced, and I am replacing the carrier bearing mount with a fresh piece of plate that has a bit more material to make up for the material lost when I cut the old mount off the frame. I also have bushings on the way and I’ll most likely finish this next weekend.

I will drop the fuel tank today to replace the rollover vent valve with a larger one. Hopefully this will allow me to fill the tank at the gas station. I also have some wiring to fix that I left loose and got melted against the exhaust. Oops.
 
Mike Shull said:
No doubt! I do have some work left to put it back together, but I should be on track to take it to a trail by late spring.

I am having my intermediate shaft lengthened and balanced, and I am replacing the carrier bearing mount with a fresh piece of plate that has a bit more material to make up for the material lost when I cut the old mount off the frame. I also have bushings on the way and I’ll most likely finish this next weekend.

I will drop the fuel tank today to replace the rollover vent valve with a larger one. Hopefully this will allow me to fill the tank at the gas station. I also have some wiring to fix that I left loose and got melted against the exhaust. Oops.
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Can you drop the carrier bearing another inch or so to clear the exhaust better? Maybe put a cv at the t-case and help with that angle.
 
A double cardon sounds like a good idea at the t case, especially if you’ve got opposing angles now up front.
 
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