The Story Of A Cummins Suburban (Lots Of Pics)

[mosesburb]

Progress has been occurring lately, but I have not shown any pics to prove it. I pulled my temporary "bellhousing crossmember" out amd installed the empty transmission and transfer case to see what was going to work or, in my case, not work. I figured doing this part with empty components would be better seeing as how I can't lift either component when they are loaded with more iron. The components actually fit fairly well. I did have to modify the floor pan a bit to get them up high enough. I had a cutoff of a 4 x 14 glue-lam that I put on my floor jack and ran up into the floor behind the trans hump. I applied some upward force to it, then I got inside with a heavy rubber hammer and beat the outer edges of the former flat area down to form a nice raised section behind the hump to produce a very factory appearing raised area. Directly behind the hump and in front of my modification is a very low valley. This had to go. I cut it out then I laid some sheet metal over the hole and formed it to make an extended trans hump. I welded it to the removable hump and screwed it to the floor behind the hole so the hump could be removed if necessary. All this resulted in me being able to install the trans and case fairly level in the chassis.



A little side note about the transfer case. I had been searching everywhere for a round pattern '205 to no avail. I had found an empty, NOS housing on ebay and I emailed the seller to find out what shipping would be, then went out in the shop to get some more work done. Well, in the mean time, my wife and boy got home. I realized that they had been home awhile and my boy had not come out in the shop yet. Hmmm, what is he doing?? So I go in the house, walk past the computer room and HOLY COW!!!! There are a bazillion error messages on the screen and my boy is sitting in front of it.
I figure I should try to undo whatever he got into. I start closing the error messages and get into a whole bunch of ebay messages stating something to the effect of: "Sorry the item you wanted to buy now has already been sold" Cool, I really did not want any....Dana 60 knuckles for a Ford. I close about twenty of these message windows and come to the last one that states "Congratulations, you won this item!!" Oh no!! What did you just buy me?!? It turns out, he clicked the buy it now button on the NOS round pattern housing. Well, I hope shipping isn't too much there boy. Turns out the shipping wasn't too bad, but the case was a bit higher than I would have liked to paid. Oh well, I have it now.

So with my floor modified, it was time to start assembling the components.

Mainshaft stack-up:



Major parts in:



South Bend clutch and Advance Adapters bellhousing installed:



I tried a couple factory crossmembers that did not work--of course. So I ended up making my own with two pices of 1" round tubing and plated with 1/4" flat plate. The part the trans mount bolts to is what is left of a piece of 2 x 3 .188 wall tubing cut to fit the angle the crossmember sits at.

Here is an installed pic:



Somewhere in amongst all this, I built the exhaust system. It is a 3.5" mandrel bent system. I got some straight pipe and 180* U-bends and went to town. It turned out pretty good. I wish I could have found some smaller radius bends than I had, so the little "pie" cuts would have had some more curve to them. They look like little pieces of straight pipe when they are installed. Hell, I probably should have just made them out of straight pipe--it would have been alot easier than cutting a specific size piece out of a bent pipe.

While I was making the system, I decided to punish myself a bit more and make one section of it twice--one witha muffler and one without. That way I can remove the muffler and offend at will whenever I feel like it. The sections look different, but they are actually the same as one is standing straight up and the other is leaning against the wall.



Someone mentioned exhaust pipe clearance around the transfer case. I ended up with about 1.5" above and below in this pic (although it does not show it too well).



In my initial plan, I was going to need a two piece drive shaft due to length. Well, as it worked out, I had to run a one piece because I had a lot less room than I initially thought I would have. No biggie, other than I had bought a super-nice two piece shaft out of a late model. I really did not want to scrap this shaft so I found the driveshaft company that I have used for the past 18-20 years. They had moved, but I located them and one of the guys still worked there. I explained what I wanted to do and he said it could be done. What I had him do was take the front half of the two piece, swap it end-for-end, knock the carrier bearing off and machine the ends so it could be re-tubed with the heavier .083 tubing. It worked out perfect and he said the factory Spicer u-joints were still in great shape, so he left them in rather than selling me new ones.

Here is what I ended up with:



Here is a close-up of the slip joint. The inner race of the carrier bearing had to be left on for the slip joint bootie to fit correctly. It is a sealed bootie, so no dust/mud will be able to enter.



So, some of you keeping score at home may have realized that the necessary components required for this yard ornament to move under its own power are present. Now, for legal reasons, I can't say that it has been driven even around the block once [cough] or six times [/cough], but if I had I bet it would have ridden pretty damn rough for the first lap with those tires being so flat-spotted. The second lap probably would have found the tires to be more round and be able to feel out the vehicle a bit better. The third through sixth laps, I would assume, would have been very enjoyable with a contest between me and my boy to see who could fit a bigger smile on their face and knowing my boy, he would have asked to go fast again. Now of course the interior is basically missing, with the seats sturdily retained by the awesome power of gravity and there are a pile of seatbelts in there, so it would have been wise to stay in the immediate vicinity of my house, never leaving the nighborhood and never going past third gear, but I would never do such a thing......

Can we go around one more time dad?? Uh,..........OK!!!!

[Palf70Step]

Nice. Been there done that. One of my neighbors used to be a local law enforcer. His eyes would sort of just close and make some comment about dreaming that something was on the road that shouldn't have been and he knows will disappear when he wakes up.

[Skirkpat]

Quality time with your boy, can't get any better than that.

[gerfunken]

This is awesome work. I'm constantly intrigued by dropping a diesel into my '72 k-20, but haven't worked up enough courage to do the conversion yet. I'm in the Phoenix area as well, and would love to see the work that you've done, as well as hear it run.

[mosesburb]

I have been getting a few things done here and there. It is tough getting the gumption up to head outside when the temp is 287 degrees F in the shade. The needle on my swamp-ass-o-meter broke off a couple months ago and its done nothing but get hotter. I have been working on the vinyl floor and other interior type stuff, but I will discuss that once I have it figured out and/or done.

I got a front bumper on it. Mine was pretty destroyed from the frame shop, so I picked up a similarly weathered unit that looks like it has been on there for years. I did discover that it had to be notched to clear the '73-'80 tow hooks that I put on it. I knew it would need to be notched, but it was more than I expected. It ended up being about a one inch notch. No biggie for me, but if someone is viewing this as a cost effective alternative to the gold-plated correct hooks, just know that the bumper will need clearancing.

The parking brake cables on the 14FF were not going to work with the lift and the '72 brackets. I need to address this issue because I need a parking brake. The pinion seal has needed replacing for many years and I need to swap the original G80 Gov-Lock unit for an open carrier with a Detroit Locker in it. I guess it is time to tear into the rear axle.



I was glad to see the ring and pinion were in fantastic shape. The backlash was in spec, so no need to replace them. I pulled the carrier out and was going to go after the pinion seal. I was going to check the pinion preload, but decided against it because it woud have been a waste of time. There was some, but nowhere near enough to bother checking. Luckily, I had enough foresight to realize this would probably be the case and I had all the pinion bearings on hand. As I was pulling the pinion support out, the UPS dude showed up with my two crush sleeves and shim kit. I always have two crush sleeves on hand so I can get the preload right the first time. I found out years ago that if I have only one, I go past the specified preload and have to go get another crush sleeve. I got the pinion support assembled and installed. I got the Detroit installed, set the backlash and sealed it up.

Then I started on the parking brake cables. Years ago while killing time thumbing through a Delco catalog, I bought the longest brake cables with the two-bolt mounting that the 14 bolt uses. The are about five inches longer than the ones I have. I tried sizing them up, but they would not work. I had entertained the idea of converting to the crossover cable that the '83 and up use, but figured out a way to get these to work.

Length comparison:


I took the bracket that was bolted to the upper flange of the frame rail and was trying to figure out a way to make it work. It was not working well until I too the one from the right frame rail and tried it on the left side. BAM!! Right there. Perfect. A little bit of cutoff whell action with some welding thrown in and I have a bracket location that nets me about 13-14" of droop before the cable becomes a limiting strap. These springs will not be capable of anywhere near 14" of droop, so it should be fine.



While I was in there I changed out the one ton spring mounting plates and u-bolts for 3/4 ton plates/u-bolts. 3/4 Ton units can be seen in previous pic.



So, nothing too exciting, but progress is being made--I can park it on a surface that is not flat now!!

[Long Roof]

At least you haven't stalled out on the project. Even at slow, things are still moving forward. This is a great build so far. Can't wait to see the sub belching black.

Can't believe the heat you guys in the southwest have had to deal with this summer. Its been the exact opposite here in the rust belt. We've consistently had low to mid 70's all summer long. I love it myself but you could never imagine all the local people *****ing that its too cold to use their pools.

Stay cool!

[jbclassix]

Are you using an original dodge version NV4500? Just wondering if you have taken care of the spanner nut on 5th gear issue? Of the 2 transmissions I have had, both have had the nut back off, one stripped the splines on the mainshaft and 5th gear. Green locktite and a staked nut has kept the second together since it came apart.

Love the build!

[mosesburb]

No, it is a GM 4500. I converted the front of it to the Dodge HD input shaft and bearing retainer. I had to have the pilot of the bearing retainer where it fits into the trans case machined down to fit into the bore of the GM trans. Both the GM and Dodge use the same input bearing, but the Dodge has a heavier "ring" around it.
As far as the 5th gear nut, I am using the GM setup that has the vibration damper on it. I discussed the matter with Dan at Quad 4x4 and he said that if the gear and the damper still have a heavy press fit, I should be ok. I am not towing anything heavy with it, so I put a bunch of red loctite on it and with a new nut, torqued the snot out of it--325ft/lbs is a ***** even with the case strapped to the bench.

[mosesburb]

I changed out the tires and wheels. The BFG mud tires had been sitting for many years and were starting to crack in the sidewalls. I had nine (yes nine) tires given to me awhile back, so I picked up some stock steel wheels from tkorinek, and had them blasted. I brought them home, painted them and had the tires mounted up on them. I also scored some stock 3/4T hub caps from him some time ago. I threw those on it and ended up with the "old man" look to the truck.

They are not too sporty, but I am really liking them. It reminds me of what these trucks looked like when they ran around back in the '70's.

Maybe it's just me??

[t korinek]

Man thats a lot of good work you've done, first time checking your build out. Those wheels look a lot better than when they left my yard!
Tom

[jbclassix]

Sounds like you got a bulletproof transmission!

[mosesburb]

Originally Posted by t korinek

Man thats a lot of good work you've done, first time checking your build out. Those wheels look a lot better than when they left my yard!
Tom

Thanks!! Yeah, there was a bit of work involved in getting them looking decent. Man, I had the theme from Sanford and Son playing on the drive home from your place with that last wierd load.

Originally Posted by jbclassix

Sounds like you got a bulletproof transmission!

I sure hope it is.

[mosesburb]

I got it emission tested and got plates on it last week. Passed the test easily. I also got the windshield replaced (I have gotten pulled over for that before). So, other than wipers, this thing is legal.

After I got the glass done, I had to go to the parts house to get something and there is a hundred and one ways to get there from where I was to where I needed to be, so I chose the freeway. 6500lbs of untested iron at speed--what's the worst that could happen?? It drove nicer at 60-65 than it does at 40 around town. It drives real nice with the "old man" tires on it. It gets from 55-75 quite quickly, hehehe. When I first drove it it was pretty squirrely, but it got much better after I re-centered the steering box and clicked the front shocks up a notch.

It runs pretty good. It has decent power, but I need to turn at least one screw on the injection pump. Low boost fueling is lacking. There is a small amount, but not so much to make it a barrel of monkey to drive. It is a simple mod, but right now I am concentrating on a few other things, so it will come in time.

I aam getting close on some creature comfort type things, so hopefully I can post up some progress real soon.

[mosesburb]

I actually have a bunch of pics to post, but my photobucket is at its limit for the month, so I have to wait for about a week for it to reset to start with the pics again. I have got the interior mostly done. The wipers are on it. There are a few little things that I need to do to it, but I have gotten most of the big stuff done.

I held off starting to drive it because I knew once I started, that would be the end of working on it for awhile. I was right. All I do is drive this thing now. I have somewhere around seven or eight hundred miles on it. I drove it to work everyday for about 2-1/2 weeks. The A/C works good at 110* and it works great below 105*. If it is under 100* it will freeze you out even without the rear a/c on.

The interior noise level is acceptable. I was worried about droan, but it is not too bad at all. The ONLY squeak/rattle is coming from the rear tail gate and hatch. I have new weatherstrip, but I am going to save that for the replacement gate and hatch that I have for it. I actually put some generic weatherstrip on the two parts and that quieted it right down.

I filled it with fuel and weighed it. Anybody want to take a guess at its weight and mileage??

[gerfunken]

I'll guess 7200 and 20 MPG.....

[pickup67man]

Love the idea of a diesel in an older Chev. Have a new Chev with a Duramax and an old Chev and like the idea of mixing the two.
I'd say you are 6500 lbs and 25 mpg.

[ldg72chevy]

What did you use for a speedometer? Doesn't the NV4500 have a electronic sender?

[mosesburb]

Originally Posted by gerfunken

I'll guess 7200 and 20 MPG.....

A fuzz high on weight, but close on mileage. My K30 DRW 6.2L with three full tanks of fuel was right at 7200lbs.

Originally Posted by pickup67man

Love the idea of a diesel in an older Chev. Have a new Chev with a Duramax and an old Chev and like the idea of mixing the two.
I'd say you are 6500 lbs and 25 mpg.

Now you are close on weight, but high on mileage. I guessed 6500lbs myself and we were both 80lbs off. It scaled right at 6420lbs and the first tank of fuel netted me 19.5 mpg. There was a 95mi round trip of highway driving on it. The next tank of in town and significant rush-hour traffic with a/c netted 16.6 mpg. My major problem is I have WAAAAAYYY too much gear. I did the math and *ideally* I should run 3.23 gears. Now I would not go that high, but I have a complete 3.54 D70 out of a Dodge with a Cummins, but I started investigating the cost of freshening it up and then re-gearing my D60 for the front and figured for that amount of money I can buy a bunch of fuel, so for now the 4.10s stay. A higher gear would make it more fun to drive though.....

Originally Posted by ldg72chevy

What did you use for a speedometer? Doesn't the NV4500 have a electronic sender?

For a 2wd trans, you would be correct. With the 4wd setup the speedometer is driven off of the output shaft of the transfer case so it has a cable just like stock. On slight side note, with my calculated guess of drive gear and driven gear I am only one mph off at 50 mph. I'll call it my awesome ability at estimation and calculation, but pure luck probably played as much of a role as my calculations did.

[jbclassix]

Unfortunatly if you want to keep the 14b the highest match gears you could use are 3.73s. I dont blame you on not wanting to use the Dana 70. I know it is a beef of an axle, but every one I have come across has been a PILE.

I had the same problem when I lifted my 6.5l 96. I wanted 4.56 gears and 35's for wheeling, but that made me tach out at 75 MPH and 16 mpg with propane. She could pull ANYTHING though! Have you consideded a Gear Vendors Overdrive? You could split gears for even better fuel mileage!

[LOW DOUGH]

I realy like what you have done to your burb! Can't wait to see more pics!

[JeremyPenner]

nice project! mo pics!

[Jtrux]

Very nice, love the wheel/tire combo, same ones I purchased for my blazer.

[mosesburb]

Well, I can't find the pics I want to post, but I have been driving the hell out of this thing so I figured an update is due. With the price of diesel fuel and the mileage this gets, it is the most economical vehicle I own (never saw that coming).

Had a minor major issue awhile back when the anti-rotation strap on my fan clutch, which was designed to always be in tension, went into compression for some unknown reason. When this happened it bowed the strap enough for the fan blade to hit it and shove it into the radiator wrecking the fan and putting a pinhole in the edge of about six tubes of the radiator. Not bad. I drove it home, tore it down and took the radiator to get fixed. Well the repair did not go so well and the core got ruined, so I ended up buying a new radiator. The fan blade got dinked up a bit, so I got a new one of those also. I went with a small block fan this time as the big block fan took so much power to turn and even above 110* the fan clutch never came on for temperature--it only came on for the a/c pressure or by the manual switch. It was horrendously loud also. The one thing I did not check was how overdriven the fan pulley is on the Cummins versus the big block. At about 2k on the Cummins it sounds like about 5k with the big block. I will not know how well it works until next summer, but for now it is fine as it never turns on with the current temps. I replaced the anti-rotation strap with a piece of 1x1/8" flat stock with steel locknuts on the ends so it can move without destroying what it is bolted to. The thing I wonder about this carnage is why it waited 1100 miles to happen. Oh well.

Then last week, I get off the freeway towards work and notice I can't see out the back window very well. Hmmm, it was not that dirty when I left the house. Hmmm. What could do that?? Hmmm. I get to work and look underneath the truck and the whole underside is dripping what appears to be enigne oil. Oh my, this can not be good. It wasn't. Come to find out, the input shaft seal on the injection pump decided to take the day off without telling me, allowing fuel to flow freely into the crankcase. I had it hauled home and picked up the seal the next day. I actually picked up a pump reseal kit. It has a bunch more parts than a q-jet kit and only cost $19.50. Got home that night and pulled the injection pump out to change the seal. While it was out, I removed a child-proof cap off of one of the adjustment screws on the pump and gave it a couple turns in. When I drained the oil I figured I should use a five gallon bucket just in case it has way more than the 11qts of oil. Well, it did. I drained SIX GALLONS of liquid that looked like oil, but flowed and smelled just like diesel fuel out of it. I checked with a friend of mine at a heavy truck dealer and got his recommendation on an oil change interval and what to look for. He said watch the blowby and the oil pressure. My oil pressure had dropped significantly, but I did not know if that was due to bearing issues or just no viscosity.

After the oil change, my oil pressure is right where it used to be and there is no blowby to speak of, so I would say the bullet got dodged. When I reinstalled the injection pump, I advanced it a bit and that, coupled with the turning of the screw that no longer has the child-proof cap on it resulted in a whole ton more power--holy cow. This thing moved before, but it flat hauls now. Running down the freeway seems like it requires less effort and the whole sound of the motor has changed. All that from an advance and turning a screw a couple turns--wow.

So all seems well now. Runs good, drives good. I am getting the D60F put together, so that should be going in soon hopefully.

[Big J'72 GMC]

wow, this is now my bible, have read the whole thing about 3-4 times now, hope it goes half as well for me as it did for you, prolly wont, luck isnt my best feature

[LOW DOUGH]

Originally Posted by mosesburb

it is the most economical vehicle I own .........This thing moved before, but it flat hauls now.

That is just awesome!

Glad everything turned out well.