My 78 K15 High Sierra build - Fish Tremble

[rgunlock]

BUT... mounting the axle brought up my next problem. Some time ago, when trying to get my steering better, I'd installed a couple 2 degree shims. That seemed to help, but not great yet.

So, while I had it all apart anyway, I thought I'd install some 3 degree shims to get my caster up around 10 degrees. The shims were thicker so I had to use the new bolts that hold them together with the leaf springs. No problem, install and cut off excess. Go to mount the axle and the driver side fits into the pad on the axle fine. Can't get the passenger side into the hole. Screw with that for a LONG time jacking things up, yanking the axle around, getting in with a pick to find the hole, etc. Wouldn't go in. Finally realized that the round head on the bolt holding the spring pack together was too large to fit into the hole. Ended up having to pull everything back apart and grinding that head down so it would fit. Wish I'd have checked that beforehand, but well... Pictures show that the axle pads have different size holes, the driver side elongated. I'd never noticed that. Probably best to get the passenger side in first and driver side would be easier to line up. Lesson learned...

[rgunlock]

At this point, I finally have the axle installed with new ball joints - progress! Time to connect everything to it.

I'd installed new brake calipers earlier that in my wisdom I decided to paint. Didn't think about removing the bushings the bolts go through first. Forgot that they needed greased also, so I had ended up with squealing brakes. Took care of all of that properly this time and it has been quiet so far.

Went to install the front driveshaft. The same shop that gave me 4.56's for the rear instead of 4.10's installed a new yoke on the front axle. Didn't give me the "U" shaped straps that bolt to it to hold the U-Joint. Originally I had a yoke with threads for that, new one needed different straps that use a nut on the back. Of course I didn't have those so ended up just removing the front driveshaft for now. Will have to find the right "straps".

Then I went to install the center link - I think that's what its called. Its the long bar that connects the steering knuckles on both sides. Originally, mine had installed from the bottom up with studs pointing up and nuts on top. With these K5 knuckles, the taper forces you to install with the tie rod studs going down. Of course, there isn't enough clearance to do that if the axle is installed because the leaf springs are in the way. Off go the u-bolts to lower the axle and get that on. Then of course, since the crosslink bar is a couple inches higher, the brackets for the steering stabilizer won't work as-is. Had to disassemble all that and figure out a way to rearrange so it would go back on reasonably correct.

Everything else went fairly well Got to drive it to work today. Steering seems a little off. Not sure if the 3 degree shims did that, or I just got used to driving my wife's Tundra (that drives better than my K15 on its best day), or moving the crosslink up and different knuckles messed with my toe setting. But, nothing fell apart so I'm calling it a job well done!

Next up, the NV4500 swap. Thinking based on this experience that I better not plan on it being a weekend job

[boynton]

Geez. Glad your persistence paid off.

[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.

[rgunlock]

Next up, pulling the bench seat so I can pull the carpet back and get the transmission hump removed. I hate pulling stuff apart that I've already completed. In this case, the casualty was the fitting on the bottom of my Vintage Air unit for the drain hose. The hose VA had sent didn't fit and I couldn't get it to stop leaking so I had gone hunting for another hose that would fit tighter. I ended up using a piece of air compressor hose, but I had to heat up the end to get it to stretch over the fitting. The hose went out through the carpet so it had to be removed. I didn't think about all that stuff when trying to remove the hose. I yanked and twisted it too much and broke the fitting I still have to figure out how to fix that.

Then move to underneath. Pulled the driveshafts, the NP205 that was already in the truck, the SM456 and bellhousing. There are a few other things in the way like the manual clutch linkage, emergency brake cable and speedo cable that also had to be removed/moved. Pretty much standard stuff for this step.

I also discovered a 2nd casualty. My speedo cable was burned through pretty badly. I think that this was from when I originally routed the cable. With my current cable routing, it didn't look like it should contact the exhaust.

[rgunlock]

I guess I ruined the "time lapsed photography" effect by not finishing my update last night. Got distracted by grilling and eating dinner.

Installing the transmission turned out to be relatively straightforward once I figured out the tilt mechanisms on the jack. Even though I have 4" lift, I also put the front up on jackstands. Wasn't quite enough. I ended up having to start with the NV4500 laid over on its side until centered under the truck, then wrestle it upright.

The NP205 - not so much. That one was a real PITA. Using wood scraps to kind of cradle it on the jack in the correct orientation ended up working, but that was after having it fall of the jack a few times while I tried to line it up. It didn't help that it wanted to occupy the same space as my exhaust on the passenger side of the truck. I also had to undo the crossmember and lower the rear of the transmission. It worked out that the tcase did mount, but the ORD brackets were pushing right up on the exhaust. Floor jack and some wood blocks just behind the bend in the exhaust coming out of the engine bay took care of that. Got myself about 1/4" clearance and no "apparent" damage done.

My transmission cross member originally had the spacers inside the frame rail so that the crossmember itself bolted directly to the bottom of the frame. Because of the clearance issues mentioned, I used those spacers to lower the crossmember. I need to attempt to measure my driveline angles more accurately, but it looks like lowering the crossmember allowed the transmission angle to be parallel with my rear axle pinion at about 3 degrees down.

[rgunlock]

AA includes a block (square tube) to mount the adapter to the transmission crossmember. In my case, it would sit a couple inches too far back. I didn't want to move my crossmember rearward a couple inches because that would interfere with the hangers for the emergency brake cable.

So, I stole an idea from DirtyLarry's thread and welded a piece of 1/4" plate to extend the bracket forward. Added a couple of gussets as well. On the AA block, apparently you were intended to use short bolts fed up from inside the square tube and obviously have limited access for a wrench. I went ahead and drilled those holes through and cut some spacers for inside. Those may not have been necessary. I doubt the square tube would have collapsed.

Also, the threads in the adapter did not hold up to even torque things up once. Ended up finding bolts long enough to go through and use a lock washer and nut at the top. I also recall DirtyLarry having an issue with this and using the same solution.

The extended part of the mounting block got holes drilled and mounted using the poly pads I already had, although I did have to use shorter bolts than original.

[Greenlee]

It’s coming together slowly but surely. Nice work!

[rgunlock]

I mentioned earlier that I had the AA bracket to mount a slave cylinder for a hydraulic clutch, but I never got around to sourcing the pedal assembly for the hydraulic clutch and I never ran into any builds that mentioned modifying the assembly for a manual clutch to work with hydraulic. So I decided to stick with a mechanical clutch.

Of course, I didn't notice that the AA bellhousing I have had no place to mount the ball for the z-bar. I ended up ordering AA's Mechanical Clutch Linkage Bracket 715534 which worked out pretty well.

I also discovered that the clutch fork push rod that I had for the SM456 setup was too short for the way the AA fork mounted in the AA bellhousing. I had a fancy LMC clutch pushrod setup with heim joints that I wanted to keep using, but couldn't find 3/8" fine threaded all-thread at my go-to hardware store. So I ended up making my own with what I could find. Seems to be working, but I think I will continue to search for a single piece of the correct all-thread since I'm not sure how much I trust my welds for this task.

One unexpected side benefit of this is that my clutch pedal now sits closer to the firewall. It used to stick up 3-4" higher than the brake pedal and I had to cock my knee sideways to work it so I wouldn't bump the steering wheel. Now its right down there with the brake pedal and much more comfortable to use.

[rgunlock]

Originally Posted by Greenlee

It’s coming together slowly but surely. Nice work!

Ya snuck in on me Greenlee. It's pretty much done, just taking me a long time to get it all posted and I'm about to head outside to start some charcoal for dinner again. Hope to get this thread caught up tonight though.

[rgunlock]

There are a couple of more things I still have to work out. The reverse lamp connector on the NV4500 doesn't match what is on the SM465, so I have to figure out what the NV4500 connector is and where to get it. First pic is NV4500 connection and 2nd is SM465.

Also, I should have noticed but I didn't. The t-case yoke for the front driveshaft is different from what was originally in my truck. The t-case came from the '76 Blazer donor and it's front driveshaft may have survived my purge to the metal scrapyard a few weeks back. I'll have to hunt around. 3rd pic is yoke for the '76 tcase and 4th pic is the front driveshaft that came on this k15. I may be better off swapping the current u-joint yoke for the mounting plate from the original t-case to be able to use the double cardan joint (?) driveshaft to deal with angles, but from reading up it is apparently a pain to change these.

There was also a pleasant surprise with this '76 t-case. After installing a new speedometer cable and test drive, I found that my speedometer is now matching nearly dead-on with my GPS so apparently I don't have to deal with figuring out the right correction gearing for an adapter!

[rgunlock]

Filled up with Amsoil synthetic fluid - 4 quarts through the shift tower. Says it is for the NV4500 and I've read that others have used it with success. Also finished up connecting and adjusting the linkage for the NP205 twin stick shifters.

[rgunlock]

Then did some significant carnage to my transmission hump. Neither the NV4500 shifter or the ORD twinstick shifters came close to going into the original holes in the hump.

The NV4500 shift tower comes up almost entirely behind, but in line with the hole for the SM465 shifter. The ORD twinstick shifters are off to the passenger side to the point that they barely clear the hole in the floor. This did allow me to maintain the mounting edge of the hump, but I'm really wondering how I'm going to mount the boot for these. I think I'm going to have to curve the mounting plate, but the angle on the boot??? Haven't tried a test fit yet though.

Bunch of pics showing what had to be cut and clearances.

[rgunlock]

With things more or less back together, the last pic shows that I have plenty of clearance between the shifters and the bench seat. Couple of random "done" pics as well.

So I still have to:
1) Figure out how to fix the AC drain without having to pull the unit preferrably.
2) Find the right connector for the reverse lamp and wire it in.
3) Figure out what to do about the front driveshaft.
4) Patch the gaping holes in the transmission hump.
5) Toss the carpet I spent so much effort in patching up after butchering it around the shifters the first go around. No way the boots are going to cover the original holes. I'm thinking I may go with rubber/vinyl flooring rather than carpet. Also get the shifter boots modified and mounted.
6) Redo the front mounts for my nerf-bar steps. The support bracing I originally made mounted to the transmission crossmember which is now more than an inch lower.

All in all, this turned out to be a pretty hefty project. I think from now on, if I can't do this on a bare frame I'll pay someone else. Just getting to the point where I don't want to deal with the up and down, crawl under crawl out stuff any more.

Test drives so far have been mixed. The transmission shifts nice although it has a pretty notable "clunk" from the topside while doing it. It sounds pretty good (reasonably quiet) from 2nd to 4th (haven't used 1st much). 5th gear is noisy as hell though. It has a fairly loud high pitched whine/drone but seems to quiet down a bit after being in 5th for a while. It also has a metallic rattling noise in 5th. That may be present in the lower gears as well but it isn't nearly as noticeable if it is present. A lot of that might not be too bad if I didn't still have the gaping holes in the hump right over the transmission and had padded carpet/mat and boots covering it up. Speaking of which, those holes make it damn unpleasant driving in Houston in August with what feels like 120 degree engine heat blowing up and into your face. Going to have to deal with that right away!

So, once I finish the list above, its just down to some tweaking and tuning. I don't have any plans for any other major changes. Just want to drive the heck out of it!

[Greenlee]

Hope I didn’t mess up your time lapse sequence with my post.

Have you tried threading the reverse light connector from the old transmission into the NV4500? I don’t know if that would work, but they sure look similar in the pictures.

That’s a bummer about the carpet. I used the rubber mat in mine and don’t regret it. I like being able to just sweep it out when it gets dirty.

[rgunlock]

Nah, you didn't mess anything up. Just glad you're still tracking this old build.

I thought about just swapping out the switch but figured I had better do some research first. It looks like if I keep the existing NV4500 switch I'll need to get Standard Motor Products S712 pigtail for it.

Do you recall where you got your flooring? Did you install it yourself and did it go in relatively easy? Did it come with sufficient jute or other padding to help cut noise and heat?

[swamp rat]

What a project! Looks like things are getting worked out nicely! I couldn’t help but think back to the early 90’s when you were posting about jacking that NP205, last time I pulled mine I had a small floor jack, I got it out okbut it fell over after I got it lowered, then I couldn’t even get it back on the jack to raise it back in place, I had to roll the thing up onto my chest and press it up and into place, took 3 attempts but I got it finally (4” lift as well). PITA!

[rgunlock]

haha, yeah when I was 30 I wouldn't have thought twice about just bench pressing the NP205 up into place. I seriously thought about just trying to lift it already attached to the NV4500 but thought the balance would be so off I might not be able to lift and line it up. I suspect it would have been just as big a PITA either way.

[Greenlee]

Originally Posted by rgunlock

Do you recall where you got your flooring? Did you install it yourself and did it go in relatively easy? Did it come with sufficient jute or other padding to help cut noise and heat?

I got the rubber mat from LMC. They have two styles. I got the one called OE one piece replacement. I put it in. I don’t remember it being too bad. You have to cut the hole for the shifter and trim a little off each side. I bought the padding from them also. It does a pretty good job keeping the noise and heat out. I remember driving around with the bare metal floor for a while. It’s definitely night and day difference from the bare floor!