Doublebase

If you have a mighty vac and you don’t want to bother with dropping the pan, you can quickly exchange three quarts out of the dipstick tube. Unless it’s the 8-speed, think that’s sealed. As for the transfer case and diffs?? Absolute piece of cake. DEX Vl for the transfer case and although the rear diff calls for 75W85, you’ll have no problem putting the 75W90 the front differential calls for, into the rear. In fact I think you’d find that a lot of independent shops would do the same. Been using 75W90 for all my doffs that call for 75W85 since 2013 (back when I owned a Lexus LS460). Never anything even close to an issue, in fact some prefer the ever so slightly heavier fluid. But this^^^entire job should take the average guy less than an hour to complete and run you $80 bucks in fluid (on the high side). That’s if you do it yourself. An independent shop might charge you $250

I'd keep an eye on that, that shouldn't have sparked unless it was a loose connection. That's generally a fool proof connection. Big wire, low resistance...a few people have complained of a spark at the starter. Was the connection loose?

Yes, very common I'd say. It feels like sort of a "fish biting" sensation...when a fish is biting your bait and you feel the rod. That's the way it felt for me, others have said the same on this forum. I think the direct injection perhaps has a little low speed pre ignition going on when the engine isn't warned up, and it goes away when it is.

And Vl stands for viscosity improvers? If so, how do those effect oil (negatively I should say)? Regarding tranny service - Looks like you’ve exchanged the fluid several times (outside of the pan drop the first time). Inline filter? Now, if you install an inline filter, will you be doing that so you won’t have to remove the pan and change the filter in the future? Or are you doing that for additional filtering? I always consider ATF “clean”...at least clean compared to other fluids on the car. I don’t think I’ve even really seen much of anything in a transmission filter. Yet I do think it’s important to change them every 50k or so. Then again I know people that have never changed them without issue (but that’s just not my style). My Avalon has 51,000 miles on it an I performed three drain and fills. Fluid was DARK. That’s the thing with Toyota WS fluid, it turns dark real fast after the factory fill. I really need to do a pan drop and filter - it’s just that I hate to do something like that on my back - usually I have access to a lift, but not due to the quarantine/virus right now. I may end up crawling under there anyway...not real happy with the results of three drain and fills. Well keep motoring, Grumpy...weather is warm, roads are clear of salt. Enjoy your summer!

Grumpy, miss you buddy. Ever since I sold the truck and bought the Toyota Avalon internet automotive land hasn’t been the same. The Toyota forums are such a BORE. Nothing happens. Especially in the Avalon forum. Wow. Great cars and they don’t really have “problems” or people that seem to want to write about the cars. So you went to 10w30 for a try? Why? You weren’t using any oil between changes on the 5w30. Have you ever done a transmission service on pepper?

This is pretty cool, nice work!

I probably missed it, but how many miles do you have? I still don't think it's a vacuum leak, a vacuum leak would cause fuel trims to go positive, not negative. And you'd feel the vacuum leak at idle, not so much when driving or shifting gears/under light acceleration, because the throttle plate opens up and the air pressure (outside/inside intake manifold equalizes, causing vacuum leaks to disappear). So I don't think it's that, although if you have a catch can you can always check your hoses and make sure. And if it was your high pressure fuel pump you'd have a code for it, plus those aren't really common problems with these trucks...torque converters are. Transmissions are. Fuel injectors are. I think your problem is in one of those three areas. And I'm in the same boat. Just a little shutter under light acceleration going up a hill on the highway. No codes (except one for five seconds, five months ago misfire cylinder 5). Hooked up a scan tool and when the "event" does happen, cylinder 5 seems to act up. It could be dirty valve, fuel injector (plug looked great, wire looked great). Only 50,000 miles. Honestly it feels more like a torque converter. Pulled pan, everything looked fine. I'll keep driving it until a hard code comes on...dealer already said they'd charge me a diagnostic fee to even look at it...I'm an ASE master certified tech, I'm not sure they'll find the problem.

Well, it has what? 140,000 miles on it? Doesn’t look all that bad, but the gap maybe looks a little big (which will happen with mileage). Definitely worth changing - I’d say 70% of misfires are going to be something simple like plugs. Got to say, I too had a misfire with the flashing check engine light. Lasted about 10 seconds, never came back but I do feel a misfire once in a while when going up big hills on the highway at lower speeds. Cylinder 5 misfire. Only 45,000 miles when it happened. Plugs looked great.

To be totally honest with you, I think your frame will last at least 15 years even if it does get totally covered in rust. As ugly as these chevy frames end up looking, I've only seen one that needed replacement (rusted through with a hole in it). Toyota's on the other hand, yeah I have seen quite a few totally destroyed. I just keep up with my frame because I can't stand the sight of frame rust...drives me nuts. I imagine at some point I'll probably tire of keeping up with it, but I figure until then I'm adding years of life to the frame/truck by doing it.

Absolutely, yes. 18’s are not immune...I have an 18, I have to undercoat it twice a year to keep it from rusting.

Breaking -- From the CDC -- Use of Amsoil products (especially Signature Series), creates Coronavirus antibodies. The world is saved. One Amsoil oil change will spread antibodies to any person within 15 feet of your vehicle. And I'm hearing that Amsoil is creating a new, even better formula called Amsoil Delta Force 9. This oil will provide protection within 5 miles of your home, without even opening the bottle. I'll post more information as I get it, but until then, stay safe, pay attention to your TBN and for the love of god, buy the best oil you can afford.

Well, just a follow up on the starter situation - which I’m sure is no secret any longer - within two weeks time I personally knew three people with these trucks that had their starters go (all under 50,000 miles). Three of them towed to the dealer. Two of them could not get the part. Guy at one dealer said, this is the worst thing he’s seen from GM in 25 years...the amount of failures and lack of parts. The starters are not sealed properly. They leak. Moisture gets in. I believe there’s a recall for it now, so if you paid out of pocket, GM should reimburse you. Don’t quote me on this. Lol.

6 speeds are no bargain either, there’s a thread on here about how the torque converter shudder tears up the pump, sending metal pieces through the transmission. Two GM techs on that thread say they don’t see 8 speeds in for repair, but 6 speeds all day long. I have the 6 speed it’s starting to shudder with only 47,000 miles (and two transmission services done to it). They both probably suck, pick your poison.

Well, I too have a similar situation with mine...2018, 47,000 miles, owned since new, 6 speed. It doesn’t like hills on the highway; if I hit a hill going slow it’ll stutter and shudder it’s way up that hill. I now have to hit hills just right, with some speed and heavy throttle, otherwise I’ll get a shudder from the tranny. I did get a check engine light once - cylinder five misfire - but everything checked out and it quickly went out. I have done two transmission services to this truck since new. Truck has been babied since day one...all highway miles. Not sure if it’s the torque converter or what...starting to think I made a mistake buying this thing.

Yeah, you guys are using Krown up there, right? Fluid Film or Woolwax seems to be popular where I am. Think Woolwax actually owns Fluid Film, go figure.

Well, don't feel too bad, guys! Friend has a 2020 Silverado and GM evidently didn't make any changes to their frame wax. The truck is less than two months old and it already has surface rust at the welds. Different looking frame though, instead of round tubes cutting across the frame in the rear, they use square tubing. Didn't crawl under it and see if anything else is different, but the rust and wax looks the same. I fluid filmed my 18 a month after I bought it...I reapply twice a year. 48,000 miles and almost two years later, it looks pretty darn good. But I don't think I should have had to gone through those extremes to keep my frame clean. It's been a real bad winter here in New England, not a lot of snow, but a ton of ice and salt. Everyday it's been a thorough salt bath.

$214.99 sounds like a decent deal...$300, not so much...and $467 is ridiculous. I know some guys that would charge you that for removing the transmission and putting it back in.

I think it depends on warranty, if they can give you a warranty with the $1,800 rebuild, I'd go with that. Because if you're going to spend $3,500 for a used transmission, there's probably a good chance you'll be having the same issue down the road (probably sooner than later). So why spend the extra $1,700?

But does that make sense to you? A vacuum issue would introduce air into the intake, the computer would compensate and add MORE fuel, not take away fuel, right? So you'd have + fuel trim, not negative. Vacuum leaks skew the fuel trim positive. And there is no PCV valve on these trucks, it's a fixed orifice, it won't get any larger and cause excess flow. You can replace it, but it's not a PCV valve. And if you did have a vacuum leak in that part of the system, I think it would cause a misfire at cylinder 5 (because the PCV line dumps right above cylinder five at the intake). If you have a catch can, potentially you may have a leak at one of the lines causing a vacuum situation, but I still think your fuel trim would trend +, not -. I could be totally wrong, let me know what you find out/how it goes.

Yup, been experiencing the same thing since day one, seems to be getting worse now. Feel it on the highway when going up an incline...truck will shutter, feels like a misfire almost (and once it did actually throw a misfire code cylinder 5). I've done two tranny services since I've owned it since new (now at 47,000 miles). Pan looked good, no metal shavings, not a lot of debris on the magnet, fluid looked good. And listen, I can live with "this", I just don't want to have to throw a transmission in it as soon as it gets out of warranty. Know what I mean? If it blows at 150,000? I guess I could be "ok" with it, but not at 60,000

Well, sounds like you’ve checked/considered everything...except fuel. Check the fuel trims with a scan tool, if it’s something like -25%...fuel is being taken away (because too much fuel is being use). Leaking injectors could be the cause.

Well this sucks, I have the 2018 Summit White as well...haven’t seen anything yet, but with this truck...I no longer believe I’ll be avoiding any of the issues because I’m special and take good care of the thing. Lol. So when it does happen, my options are touch up paint because the dealer won’t do anything?

Rule of thumb...don’t touch block coolant drains. Waste of time. And depending on the engine, you could be opening up a big can of worms if that thing snaps. You said it best, do a couple drain and fills if you’re that worried that one won’t do it. Personally I let the factory fill go to 90k-100k, then I drain and fill the radiator once. I do it again the following year or roughly every 30k miles from there on out. I consider it more a replenishing thing at that point. But I like the other method too (doing it twice). My feeling is...once you get to 100k miles, you are at the point where you probably are going to be doing some sort of cooling system repair anyway (water pump, radiator, thermostat), so you’ll be draining most of that coolant anyway.

If it’s that loud and it’s on the driver's side it’s most likely the brake vacuum pump. There’s a recall on it...take it in and get it replaced. Other than that, hate to break it to you...virtually every modern engine now is “loud”. The days of those Lexus commercials where you didn’t even know if the engine was running, are LONG GONE. They now wrap these engines in foam insulation’s to try to combat the direct injection noise. All of them have to do it. Open a hood, it’s there...the noise, the insulations. In terms of noise, the silverados I’d say are about normal/average on the spectrum...there are others much worse.

A couple weeks ago I got a cylinder 5 misfire...only lasted about ten seconds, light blinked then went off. I have a 2018 Silverado (45,000 miles, owned since new). So I pulled the spark plug...plug looked great. I swapped the coils and drove home with a scan tool hooked up to it watching live data. Had misfires here and there and cylinder 5 did misfire going up a hill once on the highway. fuel trims were -25 the next morning. Then the next morning they were fine. Ran super through and some Techron. Seems to be “ok” now. At first I thought it was an injector, but I don’t think it’d be this intermittent. A friend said the computer might it needs to be in flex fuel parameters and it’s causing some random issues in the cold weather. I’m not sure what it is, but it seems better now. Will keep an eye on it. I just think winter fuel doesn’t cooperate with these engines all that well.