Hey Vortec Guys! / Sierra pickup / Suburban / Yukon etc - Finally has Index!

justcuz

Explorer
Stick with the Valvoline, I use it exclusively and my engines are cleaner inside than outside. Years ago I bought my first Chevy Power Catalogue, It had a listing of all performance modifications to all Chevy engines. They did all their testing using Valvoline oil. Chevy engineers ran that oil for a reason.
 

rayra

Expedition Leader
welp 330 hard-run miles across the extended holiday weekend and no loss of coolant, after an initial dip after treatment. I'd say the stop leak has done its thing. Now to see if it lasts.

And I'll still be pulling the oil pan to change its gasket and the o-ring on the oil pickup tube, some time in the next several weeks. So I'll get a good look at the guts of the engine then, same as the Tahoe.
 

mr4x4

New member
thanks for the post, i dropped a pcv valve rubber piece into the valve cover, im now looking at pulling the covers and cleaning them and retrieving the PVC valve rubber piece. Also have a lifter tick so i might want to clean remove cams and clean the lifters don't know yet. But this is giving me the courage to get started, come Saturday. Different truck but similar case scenario.
 

Stryder106

Explorer
Rayra - I also put the AC Delco stop leak in my 02 Av after reading this. I've only put about 150 miles on it though. Planning on checking the fluid this week, and am also changing the pan gasket and oil pump o-ring this week. Hopefully, my leak is solved as well.
 

Stryder106

Explorer
SPARK PLUG QUESTION

Hey Guys - I've developed a low rpm stumble, so I'm going to change my plugs. I changed out my originals at 125K, now at 173K. If memory serves I put E3s in it and at the same time installed MSD wires. I'm going to put AC Delco plugs back in this time - recommended is 41-962 platinum - now here's where my question comes in: The gap spec says .060, but they come from AC Delco at .043 and AC Delco states to NOT change the gap. I called local GM dealer and he said .060. Checking online, it seems for platinum .060 and iridium .040 - BUT AC Delco is shipping them with .043.

Do I change the gap to .060 or leave them as they come at .043?
 

rayra

Expedition Leader
41-962 Delco platinums come around .40, I've been running them since last Christmas without trouble.

The spec changed over time, IIRC there was a TSB about it. All I've read about platinum is their pre-gapped and don't mess with them.
I had Delco 41-974s in the truck when I bought it, I put 41-962s in mine this past december, as per that service bulletin, and used them as they camem out of the box. My prior plugs were at ~60.

the 41-985 and the 41-110 Are/Were the Same Iridium Tip Plug, the 41-985 A/C Delco Plug has been superseded by Delco P/N 41-110.......and this change in part number was after the Below GM TSB was Published.


Service Information 2000 Chevrolet Chevy K Silverado - 4WD | Sierra, Silverado, Suburban, Tahoe, Yukon (VIN C/K) Service Manual | Document ID: 1903277 talks abotu 985s and 110s being the same Iridium plug, gapped at 40. So it seems it matters more what the plug is than what year / model it's going in.


I've done about 4000 hard highway miles on my 962s without trouble.

plugs02.jpg





On the low RPM stumble, also look at / clean the carbon and crap off the idle solenoid plunger, side of the throttle body. I think I detailed it earlier in this topic. Just spraying sensor-safe spray in the throttle body mouth and ports won't get it done and will likely make the stumble worse as it will move some of the sludge on that plunger and make it stick worse. It's 2-3 bolts, pull it, clean it thoroughly and re-install.
 
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My 2000 Silverado suffered from sticking closed throttle body when parked. Always caused a problem in the summer. Drive to the store parked it and if motor cooled down, the throttle body would be stuck closed unless I depress the pedal before starting. I cleaned it several times before I found a cure for it and it is related to the pvc oil in the intake. Under the throttle body is two coolant hoses that are to help speed up warm up time. It is done to help decrease emissions during warm up. The combination of heat and oil vapor causes a coking problem in the area that is heated which is right where the throttle blade is closest to the body. After the carbon builds up it causes the blade to stick. Removing the two hoses from the throttle body and connecting them together with a male splice. Yes it the far north with cold temps it will cause longer warm up times but here in the south not usually a problem.


We recently picked up a 2000 Suburban 1500 2WD that has over 200,000 miles and a locked up motor. After researching I am going to replace the 5.3 with an LQ9 6.0 also while I have it apart going to swap the 4L60E transmission with a 4L80E. It is a relative bolt on swap compared to some I have done. Need to modify the trans crossmember and a few basic transmission wiring harness changes. Yes the computer does need to be reflashed. Going to my local salvage pull a part yard for donor engine and transmission. Will inspect and replace engine internals. Hopefully find nothing major. Re-ring, bearings, gaskets, and new upgraded oil pump. Also will do a rocker arm upgrade as they are known to fail causing needle bearing to find their way internally. Transmission will go to my buddy that owns a transmission shop for rebuild and upgrades. Once everything goes back in it will be a like new drivetrain.

The original Suburban engine will be a donor for the Silverado as it has 270,000 on it now. The pickup has suffered since it had 40.000 miles the infamous piston slap noise. Not going to upgrade the transmission to 4L80E other than to go thru a good rebuild and upgrade clutch parts.

This will give me two good tow vehicles and 2WD with good quality tires will get me back to anywhere I want to camp. Wife hates the pickup because it is a 3 door but has 8 foot bed. The third door is suicide and a nightmare in the grocery store parking lot trying to load a buggy full of groceries in the back seat.
 

rayra

Expedition Leader
Sounds like some good projects. Were I to do it over again I'd likely go for the 3/4 ton with the 4L80E. I'm not having trouble with my Sub (yet), but I'm intendign to haul a pop-up camper trailer up and down CA in the coming year and I'm concerned it might be the death knell for my trans.


--

yesterday / today I finally got around to doing the oil pan gasket change on my Sub. Same project as on the Tahoe. Somehow it went slower this time, instead of faster.


oilpan01.jpg
/Suburban/oilpan02_zpsht29frvp.jpg
oilpan03.jpg



Looking at the flywheel and no signs of rear main seal leakage. 128k mi and 14yrs, not bad.

oilpan04.jpg



Cylinders #5 & 6, showing some scoring. Nowhere near as smooth and shiny as the missus' '05 Tahoe bores were, with 50k more miles. IIRC they're both LM7 motors. Non flex fuel. I wonder if there was a bore tech change in the later half of the model series. '03-'06.

oilpan05.jpg
oilpan06.jpg
oilpan07.jpg



Looking forward at the re-installed windage tray and oil pump pickup, over the unbolted / dropped axle. Have to drop it down to get the pan out. I changed the o-ring on the p/u tube while I had things apart.

oilpan08.jpg



Late ETA - while you have the pan off, change your oil cooler gasket (adjacent to the oil filter mount location). You can do it on the vehicle, it's accessible with the front driveshaft and exhaust downpipe in the foreground, but it would be a lot easier to change it while the pan is off the vehicle.

Now I get about a half-day's rest before tearing the front off my neighbor's '03 Tundra 4.7L DOHC V-8 to replace its timing belt, pulleys, water pump.
 
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chilliwak

Expedition Leader
I think your truck is looking good. The motor looks fine considering the mileage. I admire all your hard work tearing down so many trucks and doing all those repairs Rayra. Keep up the good work. Cheers, Chilli...:)
 

Stryder106

Explorer
Ya know - I love this thread because it gives me all the ways to fix my Avalanche - but I HATE this thread because it keeps showing me all the stuff that can go wrong with or break in my Avalanche. LOL
 

rayra

Expedition Leader
well I've had the top and bottom of the engine off, and solved a problem with the heads too. Not a lot left really. (but don't want to jinx my bearings and lifters)

Speaking of that I also ran a quart of Gunk engine flush at idle about 2x as long as recommended and it does indeed seemed to have alleviated my startup lifter noise, same as it did for our Tahoe. I do however still have a slight leak at the oil cooler attachment point / plate, right above the oil filter. It was really crudded up in that area, should have been a tipoff. I cleaned it up real good and utterly failed to do anything about it while I had the pan off. So sometime next week I'm going to have to crawl under there, remove the plate, clean it all off and slather it with black RTV and bolt it back up to cure. And I'm getting some oil seemingly from my starter bolts or above them. Going to have to track that down too.
That said, I certainly seemed to have stopped the rain from the oil pan gasket.

But most of my Sub leaks seemed to spawn when I inadvertantly did an oil change with synthetic. Leaks sprouted in several places. But too, seeing the amount of varnish and crud in my engine, it really seemed to be driven hard and not had sufficient oil changes. I'm not going to try and correct it at this late date by using a higher detergent oil. Happy enough to see no other signs of extreme wear. My hope is to finish this 'tune up' work and the (re-)lift and the electrical upgrades and finally really get this show on the road.


I'm right now in the middle of a bit of paid work for a neighbor, changing the timing belt on his '03 Tundra 4.7L DOHC. Going slow, first time handling this motor, finding lots of new and exciting ways to mash my knuckles. Bought a Haynes manual, bought the full replacement kit, did some googling and watched some YouTube vids and dove right in. I've done timing chains on GM engines many times. Been 20yrs+ since I did a chain on a Toyota 22R engine. This isn't that different, but I'm diving right in on a belt on a DOHC on an interference-design engine. A little nervous / cautious.

The neighbor had talked to someone else and got real nervous. He bought it used, hasn't done much if any maintenance on it, learned the timing belt interval was 80k mi and he's clocking around 140k and pretty much parked it. So first thing I did was warm it up, made sure it runs and then pulled the plugs - also original and with very worn electrodes - AND hard to turn out of the aluminum head with a lot of carbon on their exposed ends, lot of penetrating oil down the tubes and turning plugs in both directions to break the crud loose and limit the galling - and did a compression check just to make sure it wasn't already damaged. Everything was within 5psi of 180, good enough. Hope to finish it up tomorrow, taking pics. Maybe I'll start / add to a topic for the Toyota guys. But 'Hey 2UZ-FE Guys!' doesn't have the same ring to it.
 

Burb One

Adventurer
great job, man every time I see one of these motors opened with the type of mileage we have, I am just amazed at how well built they are, even with the oil leaks and all:)

I keep telling myself when it gets to 300k, I'm just going to replace it with a junkyard 50k, but now I'm really wondering how far they can go!

Good luck on the Toyota!
 

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