CK5
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'91 K5 Four Wheel Camper

This is the build for my 1991 V1500 Blazer, AKA the K5.3. It started out life being sold to the U.S. Government with a 350 TBI/700r4/241 combo. 4 years with a 5.3/700r4 Combo and now moving to an 8.1L Vortec and NV4500 5-speed.
Update time. Radiator is in. Larry tossed in last week when I dropped it off. We got it ready for its biggest drive yet. From his place to mine. All total maybe 15 miles at highway speeds. Larry followed so I could I didn't have to leave a ride at his place.

The ride was uneventful. We both heard some noise coming from the trans that was odd like something rubbing. We assumed it was the trans dust cover that Larry had already clearanced once already. Really the truck runs great even if the tune is not right for it. Lots of power and the exhaust sounds great at speed. The one revelation would be the ride quality. There is a section of road with a lot of large expansion joints about 20ft apart. The truck banged over each one. Larry viewed it from behind and says the rear axle just bounced over each one. Going to need to save up to get some shocks.

I got home after helping Larry dismantle a Silverado for parts and pulled the dust cover. Yep. That was the noise. We'll have to give it more room.

Good day though.
 
We had a good several days actually. With the wife and little one out of town visiting family we’ve had wrench bender for past several nights :zombie18:

It’s ALIVE!
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Runs pretty good for an off the shelf tune someone emailed me for a 6.0L that is running a 5.3L :dunno:

 
Nice video's!! It was so pleasing to actually go down the road with it. Sure we have teething issues, but it's mobile now!

In the chop shop today I helped Larry gut the interior and doors of a 2005 C2500 Silverado. I was looking at the cupholders on the center jumpseat and thought they would be perfect for the tuffy console. So I drilled out the rivets and it came home with me. I had to mock it up just to see how everything will fit. Check this out:



The cupholder fits perfectly. I was worried it might interfere with the t-case, but I cheated back a little. Going to have to get creative on the brackets to mount it.
 
Yeah the height on the cupholder is the same as the front of the box. Exactly. Almost like it was meant to be there.

Since the speedo is still not working, how fast were we going? Seemed like we were keeping up with traffic.
 
Managed to get the radio installed with the aux input this weekend. Nothing groundbreaking there. I drove it over to Larry's to grab the other seat and the old console. I did notice a weird resonance coming in when I let of the throttle, but it sounded like it was coming from the exhaust so I didn't think to much about it.

So today I take it over to my in-law's house to do some yard work which is maybe a mile from my place so no problems felt. I get done over there and decide to go out to show the truck to my buddy John with the yellow TJ heep. Motoring down the Boulevard and the resonance I heard before just changed to a major vibration as I slow down for a stoplight. Uh-oh.

I pull over into a safe spot and get out to find this:



Son of beach!

After a quick conversation with Larry via text and my niece and her hubby seeing me on the side of the road we got a plan together. I slammed down the last of my gatorade so I had something to shove over the tailshaft once the shaft is out. I had my niece pull it out of park to take the load off the shaft and was able to pull it off the rear yoke and out. I cut the end of the bottle off and shoved it over the output. I locked the hubs in and stuffed it into 4hi. The ride home was minus the resonance so that pretty much locks it down for me we got a driveline angle problem. To flipping stupid to recognize it before it broke, but live and learn right?

Closer shots of my stupidty-





Pretty sure by looking at the yoke on the shaft it's fubar'd. The groove is wiped out for the retaining clip. Need more bolts and straps for the axle yoke. I guess I'll take the shaft to work to send it off for repair. Then it's time to measure the driveline angles and get the adjustments made.
 
:haha:Told you that rear tires/axle were dribbling and hopping all over the place (to the point you could see sky under the tires) when we took it to your house last weekend and something was going to break…... The driveline angles were not dialed in and the shocks were questionable. Surprised you drive it out to PW twice like that! :screwy:The rear joint will break again until the angles are straightened out. Check the angles and see how far off it is. I have 4 degree bolt in shims I just pulled out of the Burb that should help but I bet you need more like 8 degree like the Burb needed. Phuckered up driveline angles is the downside to shackle flips. These are like the ones I have in stock. Sumbishes aren't cheap
 
Before I take the driveshaft in to fix it I'll put it back in to measure the angles. Funny thing is the 75 never needed adjustment after the cheap flip we put in it.
 
Would it not be better to run a rear double cardan joint, and point the pinion at the transfer case?

Martin
 
Based on the measurements I took tonight, we got a ways to go. The working angles are 21 degrees at the front joint and 7 degrees at the rear. Going to have to adjust both ends to make it work. Will have to see.
 
Ok, it's been a while. I haven't been sitting on my tail end the whole time. I've gone almost insane overthinking the driveline issue. Measured and remeasured and then did it again. Thought about getting a replacement shaft with a CV added to it. Larry and I talked it out and figured we may not have to go to that extreme, yet. So I measured again. Using both the GM inclineometers and an app on my phone. Here's a look at the GM tools measuring.
IMG_20160402_150517225.jpg

Here's how this stuff works. The basic statement is you set the yokes so they are vertical at the diff and t-case. Put one at each u-joint cap and slide the indicator until the bubble is level. Read the scale where the indicator lines up. In this case it's 25.5 Degrees.

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Then you take the second gauge at the t-case and take another reading. The reading here is 18 degrees. Yes the bubble is level, just didn't take the shot direct on to show it.

IMG_20160402_150541046.jpg
By using this form of driveline measurement, ideally we should have similar angles at each end. Subtract the smaller from the larger and it's off 7.5 degrees. I then remeasured using an inclineometer app on my phone as a double check. I got 3 at the t-case, 18 on the shaft and 11 at the pinion. Again subtracting the smaller from the larger between the t-case and the shaft and then the pinion to the shaft I ended up with a 15 degree working angle for the front and then a 7 degree working angle for the rear. Then subtracting the smaller from the larger and it's 8 degrees

Either way I do it the measurments it's within .5 of each other. The target is 8 degrees. After discussing with Larry the findings we plan on dropping the t-case crossmember to relax that front angle even if it's just a degree or two. I went ahead and ordered up a set of 8 degree shims from DIY4X as a kit with new center pins. The shims are steel and well built.
IMG_20160407_200656280.jpg

The Blazer will need to spend some time back in it's birthplace for the shim-ectomy. Then we can address the driveshaft itself
 
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Dropping the tcase will hurt the front shaft angles, so watch it.

I just figured out my driveline problem. I was only off of ideal by less than about 3deg and it was like riding a paint shaker. Talked to Tom woods and my working angles were in the 20+deg and they said it wouldn't hold up.

Ended up cutting the perches and shock tabs off and welding new ones on w/ double cardan. Fixed it right up. Your pinion angle's in kind of a weird spot. It's almost high enough to do a double cardan w/o moving it, or you're going to have to shim it down a ton to keep a conventional shaft..
 
Just as a comparison w/ my double cardan I think I ended up about 13.5 ish up on the pinion. I can't remember the exact driveline angle - think it was 15.3, but the rear ujoint now runs on a working angle of about 1.8 I think. If I can remember (my brains getting old) .

Old shaft was .3 down on the tcase, 22.8 down on the drive shaft, and 3.2down on the pinion - yes down (my tcase is basically flat, so I left a bit for spring wrap but overshot a hair) so my working angles were 22.5 and 26, and it shook something fierce. And this was all 1410 ujoints which should have better angle capability
 
Dropping the tcase will hurt the front shaft angles, so watch it...
We’re not talking about dropping the rear crossmember down a lot. Like around ¼ inch with plate steel as I have done on my Suburban and K10 below. No effect on front driveline angles with dropping the crossmember modestly

Suburban
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K10
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