Builds 86 Xtra Cab Build (4Wheelunderground 3 link front, 4 link rear and 3.4 swap) (1 Viewer)

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It does. And I have a Ruff Stuff back brace I have room to put on. Not sure if I will yet.

I'm waiting for the shocks and bumps. I'm also dealing with some medical things and trying to get another Toyota running so I can sell it to help fund this build.

I promise I'll get back on this soon.

No rush, take care man!
 
I decided to start checking in to my front driveshaft angles. My front pinion flange is pointing up 4 degrees. I was not happy when I realized that my front T-case flange was pointing up 6 degrees. This is at ride height.

I can't lower the engine to improve the angle but I can raise the back end at the T-case. Unfortunately I had to cut out my trans tunnel which REALLY sucked.

The best angle I can get is still 4 degrees up at the front case flange.
I put a straight edge across the two flanges and measured a 12 degree slope.

I need to call High Angle Driveline and see how I should proceed.

Here's a couple pics. I also finally cut out the bumps in the floor that were over the torsion bar adjusters. The holes just happened to line up with the FROR crossmember bolts.

You can see why I had to cut out the tunnel. I need to make it taller.

IMG_20220411_162633003.webp


IMG_20220411_162545981.webp
 
In order to have both output flanges at 90 degrees, I'll either have to lower the engine or raise the rear. I can't lower the engine without losing up travel.

I'll have to cut more floor to raise the rear and make a longer tunnel cover.

It's all tilted back 4 degrees. The rear is easy. Just rotate the pinion up or down.

I don't know what I can get away with up front. The T-case flange pointing up 4 degrees can't be good.
 
I'll consult the driveshaft experts. If I have to rotate the knuckles I will.
Its a lot easier than one would think. Its obvious you have the skills to do it based on work presented herein.
 
I appreciate the compliment. 4Wheelunderground specifies 6 degrees of caster and that's where it's at. I may have to rotate knuckles to keep it there AND get the proper pinion angle.

I'm not so worried about that. I don't know what to do with the 4 degree up angle on the output flange. I'm kind of assuming it needs to be 0.
 
I've set pinion angle for a CV shaft before but never with the (T-case) drive flange pointing up. That's what's throwing me. I don't have one to install right now to try.

I need to get one made or ordered. No good driveshaft shops in Tucson that I know of so probably ordering online.
 
Front flanges almost always point up, it's a product of the rear pointing down.

The general rule with a CV drive-shaft is point the shaft directly at the flange. In other words, all of the angle happens in the CV, the pinion U-J has littlre to no operating angle at ride height.
 
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Now that I'm thinking about it, it HAS to be pointed up if the rear is down. On my leaf spring SAS I used the front CV for the rear. I had no problem setting pinion angle. It was recommended that I use the rear for the front. Whole different method for that. It was fine all these years. A local truck shop made the shafts. Nothing special.

This build has WAY more travel and I was thrown off a bit with the front flange tilting up. The new drive shaft is not going to be cheap and it would suck to have lots of vibes. Now is the time to make sure it's right.

I sent an email to H.A.D. I'm sure they'll set me straight.

Thanks for the feedback. I appreciate it as always.
 
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I've set pinion angle for a CV shaft before but never with the (T-case) drive flange pointing up. That's what's throwing me. I don't have one to install right now to try.

I need to get one made or ordered. No good driveshaft shops in Tucson that I know of so probably ordering online.
I have used and like Tom woods driveshafts.

Very knowledgeable and helpful, quality product, fast serves and shipping.

A real person will answer the phone 801 737-0757
 
Same is true for H.A.D., Jesse is who usually answers the phone. No idea how he gets anything done.
Can't likely go wrong with either of them.
 
Just to let all know how good the customer service is, I sent email last night and Jesse called me this morning. He said I can improve angles by a cut and turn of the knuckles but, he doesn't think it's worth the effort for the little improvement I might see.
 
For reference a double cardan front drive shaft from Tom Woods it's just north of 400 dollars delivered to your door.
IMHO it's better to get the Caster correct then run a double cardan front drive shaft if the pinion angles are off.
 
Hi Broski, I just gave all my measurements to Jesse and asked what he recommended. My caster is set to the spec of 6 degrees as per Brian at 4.W.U.G. I'm leaving that as is. If I want to change the pinion angle AND keep my caster at 6, I have to cut and turn.

I haven't called Tom Woods yet. They have an authorized dealer near by so I'll go talk to them.

I agree with you about proper angles so I'm not against cutting and turning if I NEED to. I won't know for sure until I get the wheels and tires on the ground with the coils holding the truck at ride height. It's going to have to be bad before I do though. Turning the pinion up changes EVERYTHING with the 3 link brackets. Rotating knuckle balls is the easy part.

Right now I'm just trying to stay up on my build as much as possible. I have a couple surgeries coming up.

Thanks for the info.

Also, Brian got back to me about my rear 4 link parts. Looks like another month or so before I see them.
 
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Broski, I got an alert for the "like" for this post so I thought I'd update it.

Life happened big time. I'm still up on two feet so that's a plus.

I did contact Tom Woods' shop and Jesse at H.A.D. I just need to get one ordered.

Just to add, Both places recommended a double cardan shaft and said turning knuckles are too much work for too little benefit and neither recommended it.

Still waiting on the rest of my rear 4 link parts. I just got contacted Friday that my shocks and bumps are at the shop and I should get them this week. The flex joints are "supposed" to be shipped direct from Summit Machine soon. I can't really get going on the rear without links for mock up.

Just because I'm a guy that can't sit still, I have still been plugging away at the 1990 pickup so I can get it sold. Hopefully it will help pay for some wheels and tires for this build.

So that's where this build is at. I didn't give up.
 
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Just to add, Both places recommended a double cardan shaft,
I get confused with the terminology. do they mean a dual double cardan shaft, double cardan at both ends? Also, are you running a high pinion front diff? Wouldn't a castor angle of 6 degrees have the front diff pinion flange pointed downward? Stock castor is 2 deg +/- 1deg. It seems to me a cut and turn would be needed to get the pinion to rotate back up after rotating it down to achieve 6 deg not to mention how nice it would be to angle the pinion exactly how you want it.
 
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Many people call it a CV drive shaft. Many people will correct whoever calls it a CV drive shaft. Most people know what you mean either way.

I do have a high pinion diff. With my caster and 3 link brackets set as per the instructions, my front pinion is slightly up at 4 degrees at ride height.

I gave all the measurements and angles to both shops and they said "in their opinion" it wasn't worth the work for something I'm not even going to notice. I got the same from 4Wheelunderground.

I would have to cut everything off the axle housing and start over to do it. I trust their expertise so I'm not going to rotate knuckles. If I'm wrong I will be sure to post up.

If I was going aftermarket axle housing I would buy it bare and assemble as required.
 

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