My Suburban Renewal Project

[bobbiemartin]

I thought I would post my current project. We are the original owners of a 1995 Suburban 6.5 1500 2WD. I have done a a few mods through the years, mostly for reliability. On of the biggest was to convert to a DB2 pump as I got tired of the DS4/PMD problems. The pump is a 4974 marine injection pump, also has Bosch marine hi-pop injectors, GM4 with TurboMaster, HO cooling upgrade with dual stats, a later round filter air box with K&N filter and a 3" Mandrel bent exhaust. I also have a Racor fuel filter installed before the lift pump. It also has Bilstein shocks, GM aluminum wheels and a WT grille with Cibie H4 headlamps.

Its pretty much a second vehicle now and has 185,000 miles. A while back, an oil analysis revealed that it may have a broken piston ring. A subsequent oil analysis confirmed that its getting worse, so it was time to make a decision. We contemplated selling or trading it, but we really like it and decided that spending a lot of money is not a good idea right now. So I decoded to repair it. I'm on a pretty strict budget, so getting a new GEP 6500 Optomizer (my first choice) was not an option.

I found a used engine and transmission that I think was a good deal. It was supposed to be a 1993 with 130,000 miles and a Goodwrench rebuilt 4L80E with 10,000 miles. It was removed for a Cummins conversion, so I'm reasonably sure its OK. After getting the engine, I found its a 1997 506 block. I contacted the seller and he told me he bought the truck form the original owner and he never mentioned replacing the engine. I'm not thrilled about the 506 block, but I have removed the oil pan and all looks OK, so maybe it will be all right. Its going to require a few changes to make everything fit. I also discovered the new trans has a bolt on yoke, the Sub a slip yoke, so I have to sort that out. You would think GM could keep everything uniform, but I guess not. I also have a few mods planned while its apart.

I have the old engine & transmission out. If anyone is interested, I can post my progress on this project.

 

[TurboTahoe]

Hi Bobbie,

Hey, YOU BET - this group is just junkies for a thread with a build-up! Please entertain and inform us!

-Rob

 

[bobbiemartin]

Here is the Suburban

The old engine with twin thermostat & DB2

 

[ak diesel driver]

looks like a really clean burb

 

[bk95td]

Nice lookin rig. Well worth putting another engine in. Finding good used engines is tough. I've found the best deals on 599 6.2 engines. I got one out of a small bus with less than 100,000 miles for $300.
If your 97 "506" is a late enough 97 you should be ok. Gotta run what ya got. A 96 would be worse.

 

[bobbiemartin]

Just a quick update on my progress. Spent last weekend cleaning up the new engine and related parts and getting everything ready. I checked the block over and can see no cracks around the main bearing webs, so it should be OK.

I have most parts I will need on order or in hand. The injection pump & injectors are at the injection shop getting checked out. I bought a Cloyes timing chain kit and will install this weekend and hope to get most parts swapped over from the old engine to the new one.

One thing I found is that GM made a lot of changes on these things. The new 4L80E has a yoke style output shaft and the old one has a splined slip shaft. Also, the Sub has a longer shifter shaft that goes through the neutral safely switch and the new one has a short shaft. I talked to a buddy at a local dealer and I have someone that will swap the output shafts and shifter so I will have that sorted. Fortunately he is not charging me too much and I will have all new seals, etc so the transmission should be fine. I have had a PML deep pan for a while, so I’ll install that when I get the transmission back.

When doing something like this, having a good parts guy at the dealer is a life saver. The factory firewall insulator was falling apart and just crumbled away if you touched it. I found its NLA from GM. My parts guy did a parts locator search and there was only one listed at a dealership in Texas. They sold it to me at dealer cost, but with the oversize box charges the shipping was more than the insulator! I figured its now or never to replace it and since this is a Suburban, I want it to be a quiet as possible. I had hacked up my fuel return line to fit the dual thermostat and since I’m going back to a single thermostat, I wanted to replace it with a new one. That is NLA as well, but there are a bunch around. I have one of those coming as well. I’m surprised so many parts are NLA already. I guess GM is not making the slow selling parts any more.

I’ll try and take some pictures this weekend.

 

[Matt Bachand]

I see you're addiction to DTR has begun my friend! Great news for us!

Absolutely keep us informed every step of the way with as many pix as possible. You will find that posting is a way to keep track of your progress in a documented form also. When I have a re-occuring problem, I always seach back for my old posts and re-read them. It's amazing what details you forget.

I, as most of us (all of us) here will be watching this thread closely.

 

[DieselCash]

this thread is awesome, keep up the good work! :thumbsup:

 

[dangerousdave]

Welcome aboard, and Thanks for the great (so far) project.

 

[Brooklyn Tow]

A while back, an oil analysis revealed that it may have a broken piston ring. A subsequent oil analysis confirmed that its getting worse, so it was time to make a decision.

This may be a dumb question, but........Why not just repair/replace the piston/ring?

 

[bobbiemartin]

This may be a dumb question, but........Why not just repair/replace the piston/ring?

I did consider this. But I figured with 185,000 miles it would end up a total rebuild before I was done. Plus, from what I have read, most 4L80E transmissions do not see 200,000 without a rebuild. When I found the engine & trans, it seemed to be the best deal. It turned out maybe its not the greatest deal, but if all works out its still probably the cheapest way.

 

[bobbiemartin]

Worked on getting parts switched over and cleaning/painting parts. Didn't get as much done as I wanted - seems like that is always the way.

The old engine, still have the ancillaries to remove.

New engine, waiting for timing chain and ancillaries from old engine.

 

[btfarm]

That's a mighty nice looking Burb. Glad to see you here and documenting the swap. One question... have you considered pulling the heads to check them out for cracks and if nothing else to get fresh head gaskets in it? They seemed to be a problem in '97s.

 

[bobbiemartin]

One question... have you considered pulling the heads to check them out for cracks and if nothing else to get fresh head gaskets in it? They seemed to be a problem in '97s.

I did think about it, but decided not to. I did an oil analysis and there is no coolant in the oil, so I don't think its leaking. If I change the head gaskets, I would have to buy new head bolts or ARP studs. Then you figure maybe a valve job & precups and while you are doing that some rings and bearings. So I decided just go with it the way it is.

 

[07HDClassic]

That is a great looking suburban! Rigs that are that clean are getting hard to fine, thats a keeper and well worthy of a heart transplant. And the PYO's look awesome on that body style.

Keep us updated on the progress.

 

[bobbiemartin]

Well I have been working away on the Suburban. I replaced the evaporator and heater core. A bit of work to remove the dash and related components. Once I got the entire climate control assembly out, replacing the evap and heater core was easy!

I replaced the compressor and had the system flushed about 2 years ago. It never really worked like it should and the compressor was already bad. So I decided to replace everything while the engine was out. Here are the old and new evaporator cores.

The old one was full of crud, so I'm sure it would not work at peak efficiency. Since I was in there, I replaced the heater core as well.

I also installed a new condenser. It looked OK, but from what I have read, the evap & cond can plug up internally and are impossible to clean. Having a good air conditioner is pretty important in Florida, especially in a Suburban, so I did not want to take any chances. I also have a new compressor, accumulator and orifice tube. It should cool fine when I'm done.

The original firewall insulation had fallen apart. The new pads are NLA, but I found there was one (the only one) at a dealer in Texas. He was probably as happy to be rid of is as I was to get it. I will be installing this weekend.

I found GM made several changes in the 4L80E transmissions. In addition to needing the output shaft changed to fit the Suburban driveshaft, the shifter on the Suburban has a neutral safety switch, so that needed to be changed as well. I found a guy at a local dealer to swap the shifter and output shaft for me. Everything in the new trans looked good but I did get a gasket set and new seals, so the transmission is ready to go.

Shifter on the Suburban sticks out farther

Transmission rebuilt with correct shifter & output shaft.

I heard back about my injectors. I had these built with new Bosch 311 nozzles a while back. They can't have 15,000 miles on them, but they are already burned and do not have the correct spray pattern. So its new injector time. Still waiting to hear on the pump.

I hope to have the engine compartment done this weekend. On the engine, the oil pan is on and the timing chain has been replaced. If I get the pump & injectors, I should have the engine pretty much ready to instal, maybe next weekend.

 

[SuperTuscan]

Nice looking suburban.

I just got mine back on the road after a year of sitting and I'm thinking about fixing it back up a bit. Mechanically, it runs OK. The transmission does clunk a bit when you apply fuel after coasting. Other than that it seems to run well.

I need to start tracking down doors and fenders. Then, maybe the rear A/C lines get fixed.

Will be keeping an eye on your project for motivation.

 

[bobbiemartin]

Did some more work this past weekend. The dash install is complete in after the evaporator install. My dash wasn't cracked but I did go back with the Walking J rattle stops. While the dash was out, I found out why the blower motor quit working. I had traced it to a bad ground. I found a melted connector with two large wires, 10 or 12 gauge, red & black. Anyway, I could see no reason for the connector, I assume it made assembly easier when they built the truck but I didn't need to disconnect to remove everything, so I just cut it out and spliced the wires. Must draw a lot of current with the AC on. The blower should be fine now.

Dash and heater/AC assembly out

Everything back in - lets hope it all works!.

I have the new firewall pad installed. I have moved the relays for the headlights so I can mount the cruise control box on the firewall, where it belongs.

Firewall before, the old pad was in sad shape.

And the new firewall pad installed

Did a few other things, including disassembly of the GM-8 turbo that is going on. I have the injection pump and injectors back now so I can get the engine assembled this week if all goes well.

 

[bobbiemartin]

Making some progress, I have the engine about 98% ready to install. Forgot to take a picture before I put it away, but here is one during assembly.

New timing chain installed, DB2 Marine pump back from rebuilder. He made a few tweaks to the advance and fuel setting so I'm hoping for better performance. My Bosch 311 injectors were toast after only 10,000 miles, so I have a new set (not Marine high pops) installed.

I bought a GM-8 Turbo and installed a rebuild kit as a precaution. Here it is disassembled.

Its now back in one piece and on the manifold.

I had several oil analysis done on the old engine. A while back, they started showing high chrome and iron and suggested a broken piston ring, but upon disassembly the rings and bores were fine. There were no broken piston rings. However, the block was not so good. Second main saddle is cracked all the way up to the cam bearing on the right and on the left into the bottom of the cylinder. A couple other smaller cracks on other mains as well. This from a 2WD Suburban basically used as a daily driver by my wife, never really worked hard in its life. Incidentally, the crankshaft mains & rods still measured at factory specs.

I'm sure this would have made a big bang if it let go while running!

Its getting closer to engine install time, just lots of little things I have done that were very time consuming while the engine was out. I'll be away for a couple of weeks, so maybe will have it in mid December.

 

[WarWagon]

After owning a 1995 Yukon forever in AZ type heat...

AC:
Get a severe 105+ degree VOV variable orifice tube to replace the fixed orifice tube. This will get you a cooling difference you can feel at idle.

Yank and throw away that blower motor. It is internally shorted and will continue to burn the hell out of the wires, relays and resistors. I tried the eliminate the connector trick you are doing and added a ground wire from the motor to a good under dash/cab ground. It simply burned up the crimp connectors I used to eliminate the connector. :nono:

Last get a booster fan for the AC. Relay it to power on with the compressor clutch. Rock Auto sells these pusher fans as they were a factory option some years for sure listed 1993-1994 on 2500’s.

Look at the fan clutch condition and upgrade it if you haven’t already. (For AC again.)