My 78 K15 High Sierra build - Fish Tremble

[rgunlock]

Thanks, hope this didn't come across as a downer/rant update. Sometimes these projects just go like this, at least for me

[MTCK]

Originally Posted by rgunlock

Thanks, hope this didn't come across as a downer/rant update. Sometimes these projects just go like this, at least for me

It happens to us all! My wife often asks how I can be so good at estimating how quickly something will be built buy others, and so bad at estimating how long it will take me to get something done on one of the old trucks. You outlined the reasons pretty well!

[swamp rat]

Keep in mind that changing the pinion angle also changes the caster, I'd consider having a front end alignment shop check it out.

[Greenlee]

Nice work! It’s going to be sweet with the NV4500.

Are the shims needed because of the lift? Just curious because I don’t remember using any shims on mine. I guess another option would be to cut off the axle perches and weld new ones at the correct angle, but like Swamp Rat said anything you do will also change the caster.

[rgunlock]

Originally Posted by Greenlee

Nice work! It’s going to be sweet with the NV4500.

Are the shims needed because of the lift? Just curious because I don’t remember using any shims on mine. I guess another option would be to cut off the axle perches and weld new ones at the correct angle, but like Swamp Rat said anything you do will also change the caster.

Originally Posted by swamp rat

Keep in mind that changing the pinion angle also changes the caster, I'd consider having a front end alignment shop check it out.

I added 2 degree shims initially because after getting my truck on the road I had steering issues. This might have been because of the lift. The truck tended to want to go wherever the road surface took it. I had an alignment done (before the shims) and had 6.x degrees of caster and based on advice I got here on the forum I was trying to get it closer to 9 degrees. That seemed to help quite a bit, but there was still some room for improvement so while I had the axle off this time I installed 3 degree shims to get my caster closer to 10 degrees. This hasn't seemed to help, but as mentioned I changed other things that might have impacted my alignment.

Still haven't got it into an alignment shop because the underside and interior are torn down in the middle of the tranny swap It's just too dang hot in my shop to get that done by myself in a weekend.

[rgunlock]

Time to describe the swap from SM456 to NV4500. I do plan to go into a little detail here because there were a number of things I ran into that I hadn't seen in other NV4500 swap threads.

This will be like time-lapsed photography because this swap covered multiple weekends. It took a good bit longer than anticipated, but if you've been following my build you'd know that it would have been more of a surprise if it went smooth and quick

So this all starts back in January of 2012 - maybe earlier - when I started collecting parts for an NV4500 with NP205 for another project that still hasn't gotten off the ground. I got the NV4500 from a 92 donor truck and a NP205 transfer case from a rusted out 76 K5 Blazer donor. Turns out that the NV4500 is apparently a newer model that had been transplanted into the 92. The axles I've already posted about swapping came from the same Blazer. I had the NV4500 and NP205 "gone through" by a drivetrain shop back at that timeframe so they were ready to go. I'd ordered the Advanced Adapters NV4500 to 23-spline NP205 adapter (50-0218) and bellhousing 712577 along with a bracket to mount a slave cylinder for a hydraulic clutch. It all sat for years while the rest of this build went on. The drivetrain shop that did the NV4500 work also did the required cut on the tailshaft and mounted the new adapter/tailhousing, etc.

So a few weekends ago I matched up the NV4500 and NP205 for a test fit and to mount the shifter bracket, etc. I'd read that the AA bracket for the NP205 shifter was kind of flimsy and that turned out to be the case. So I added to the bracket so it would have a little more support. That seemed to work fine. But the little s-shaped linkage to the shift bar would not line up and fit at all. I ended up trying to make one of my own. It did fit, BUT I could not get both the front and rear ends of the rail to shift together. I could kind of juke things and get them right, but that wasn't going to work with the transmission hump in place and not being able to see how things were aligned.

[rgunlock]

So rather than screw around with the shifter bracket and linkage any more, I ordered the ORD twin stick shifter kit for the NP205. For the most part, this just bolted up. The instructions were pretty good but they sent it with the wrong size bolts for where part of the bracket mounts into the back of the AA tailhousing and I did have to grind a bit off the bottom of the bracket to get it to clear the curve of the adapter and allow the bolt holes to line up. I guess I didn't get a picture specifically of that part of the bracketry so the last picture is a jump ahead that actually shows it. The issues weren't a biggy - this seems to be a quality kit.

[boynton]

Time flies!

[rgunlock]

Got my rear driveshaft back from the drivetrain shop yesterday and mounted it up. Length was still fine and nothing needed replaced/rebuilt but it turns out that it was quite a bit out of balance. Man what a HUGE difference that has made. I guess that the moral here that I shouldn't have assumed that any original parts were good as-is just because they looked good. There are already enough issues to chase down after assembly is complete.

Looks like because of the angle I'm going to have to swap out the front yoke (or whatever it is called) on the transfer case to use the double u-joint style shaft. Wish I'd done that when I had the TC out on the floor. Project for another weekend...

[swamp rat]

Originally Posted by rgunlock

Got my rear driveshaft back from the drivetrain shop yesterday and mounted it up. Length was still fine and nothing needed replaced/rebuilt but it turns out that it was quite a bit out of balance. Man what a HUGE difference that has made. I guess that the moral here that I shouldn't have assumed that any original parts were good as-is just because they looked good. There are already enough issues to chase down after assembly is complete.

Looks like because of the angle I'm going to have to swap out the front yoke (or whatever it is called) on the transfer case to use the double u-joint style shaft. Wish I'd done that when I had the TC out on the floor. Project for another weekend...

Well crap, if I had noticed the single yoke in a pic you posted I may have spoke up cause the NP205 has a double Cv type joint. Now if you do that your going to have to shorten the shaft length. Trying to install the shaft with the CV joint is a bear too! Least on my truck

[rgunlock]

Originally Posted by swamp rat

Well crap, if I had noticed the single yoke in a pic you posted I may have spoke up cause the NP205 has a double Cv type joint. Now if you do that your going to have to shorten the shaft length. Trying to install the shaft with the CV joint is a bear too! Least on my truck

Yea, I got myself into a bit of a mess using this NP205 I just installed. It's a bit older NP205 that came out of a donor '76 Blazer and the front output has a yoke for a 1310 (I believe) u-joint. The NP205 I just pulled out was the one that came in my '78 and it has a front output that is a flat plate with 4 bolt holes that a CV type joint connects to. This weekend I looked into just swapping between the NP205's but the currently installed is 10 spline and the other is 30 spline so no-go.

Looks like the '76 blazer would have come with a CV style joint as well, but the rearmost u-joint just goes into the yoke on the TC rather than terminating in a round flat bracket that bolts to the flat plate style TC "yoke". Not sure if that made sense. And it looks like that shaft may have to be cut shorter.

So, looks like I could go that route, or else swap my original NP205 back in. Not sure I can do that either because the input has to match the AA adapter coupler, but haven't looked into it yet.

[swamp rat]

Originally Posted by rgunlock

Yea, I got myself into a bit of a mess using this NP205 I just installed. It's a bit older NP205 that came out of a donor '76 Blazer and the front output has a yoke for a 1310 (I believe) u-joint. The NP205 I just pulled out was the one that came in my '78 and it has a front output that is a flat plate with 4 bolt holes that a CV type joint connects to. This weekend I looked into just swapping between the NP205's but the currently installed is 10 spline and the other is 30 spline so no-go.

Looks like the '76 blazer would have come with a CV style joint as well, but the rearmost u-joint just goes into the yoke on the TC rather than terminating in a round flat bracket that bolts to the flat plate style TC "yoke". Not sure if that made sense. And it looks like that shaft may have to be cut shorter.

So, looks like I could go that route, or else swap my original NP205 back in. Not sure I can do that either because the input has to match the AA adapter coupler, but haven't looked into it yet.

\


Yea you made sense, my trucks front shaft has the round plate the 4 bolts go through, but I admit I don't know what the yoke is called it bolted too so I'll take your "TC Yoke" as the word.


Yea the joys of custom builds, hope you can verify the input shafts before you can go any further!

[boynton]

Get a quiet muffler and electronic cut outs. That’s what we have on my dads 68 BBC Camaro. It works well.

[MTCK]

Nice! Pumped you have been driving the wheels off of it. My big truck has 3.5” magnaflow with a cat in front and it is very livable. Still pretty loud when you let the horses run of course...

[rgunlock]

Glad to see you guys still keeping an eye on this.

The mufflers I currently have are Magnaflow 13215XL which have a 14" body. I had to get a new piece of exhaust pipe bent up to go around my new setup for the transfer case and dual sticks and the guy that owned the shop said that if I like the sound but want it quieter at cruise, get a longer or bigger bodied muffler. This morning I ordered a pair of Magnaflow 13255 mufflers which have an 18" body, so they are still available Mike.

I think for the wind noise I'll get some of the seals that mount to the door around the window and see if they help. The truck had some originally but I didn't replace them after paint.

As for the 5th gear howl, I've been debating a different oil. I used Amsoil which says its for the NV4500, but it isn't the OE specified oil. The right oil and additives made a big difference in the rear end. Just hate to drop the $$$ not knowing it will help. But then again, I don't know of a shop I trust to go through the NV4500 again and hate the idea of pulling it back out of the truck again. Marcus I hope your tranny is still behaving itself. I know how it is to pay for a rebuild and then discover you might not have gotten what you paid for like your previous rebuild.

Boynton, still waiting to see a thread start for the Blazer, and are you getting any sleep yet? Mike, it won't be long till the weather makes you want to get yours out and work on it again.

[Greenlee]

Glad to see Hazel is still on the road and getting the kinks worked out! I got really lucky with my vent windows. Me and a buddy had bought a 91’ Suburban for parts. He was building a K5 at the same time I was rebuilding my truck. We had just about used everything we wanted and were about to take the remains to the scrap yard when I noticed the vent windows looked really good, so I snagged them. They don’t have any wind noise at all. I later read on here something about those later model Suburbans having a different design??? All I know, is I’ve had plenty of them on old trucks in the past that had wind noise!

[rgunlock]

Hi Greenlee, I did rebuild my vents with new rubber. At this point, I'm not sure if the wind noise is from the vent or the front edge of the door. I've already "adjusted" the front window frame with wood blocks and heavy shoves. I'm thinking the extra weatherstrip can't hurt and should be a fairly easy upgrade.

Thing is, now that the truck is my daily and not my main project, things like this just have to be added to the list. If it bugs me enough, it moves up in priority

[TKCR]

Hey there Rick, hows it going. Those seals that go above the door sash, should help with the wind noise.

[mongocanfly]

good looking "new toy" ya got..!!!

[boynton]

I might know someone who has a few parts laying around if you need any! Nice buckets and console.

[rgunlock]

Originally Posted by mongocanfly

good looking "new toy" ya got..!!!

Thanks guys! Ok, actually the '78 is the "toy", this is the "work truck"

Originally Posted by boynton

I might know someone who has a few parts laying around if you need any! Nice buckets and console.

Yea, I don't know that much about the 67-72, but I would assume if this truck came with buckets and console it would be in the SPID. Regardless, they look great and to my untrained eye original so I think I will run with them. I also got lots of extra parts, missing mouldings and emblems. Not sure what other parts I might need. This one is pretty complete I think, but I know where you are if I find I am missing something

Showed my wife some pictures of the medium bronze and white GMCs and her eyes lit up and she's like "ooh, I would love to have it back in that color!". So I dunno. The '59 might be put further on the backburner and this one might be more of a restoration than I'd planned.

Its all good. Main thing is to keep me active in my weekend projects. To be honest its been so long since I got all the '59 shells and I've had so much time to think on it, follow builds, etc. that I'm not even sure at this point what I want to do with it. I've only got sheet metal (lots of it!), one a big window cab with a lot of rust and one presumably ok original frame. Wide open canvas and I have no plan! So I guess its ok to wait its turn a while longer.

[7dee2]

Nice project Rick, I'll tell you I'm still working the heck out of Blue our C30. That long bed could haul lots of stuff! . 9k wow, you are winning the mileage award, just hit 1400 on Ray mainly just using it to show off and pull the car trailer around.

[MTCK]

Sweet GMC! Glad you’re driving the heck out of your half ton.

[rgunlock]

Thanks guys. After driving the new one a bit, it has really made me appreciate how well I have the '78 running and handling, lack of unexplained noises every time you turn around, etc. I'm able to drive the '78 every day because I really don't mind driving it. The "new" 71 has a ways to go before I can make that claim about it, but it will get there.

[TKCR]

Cool Rick, I love the new “TOY”!! I’ll be following along on this one. Are you making another Build Thread for this one?