Doublebase

It's funny you mention you haven't seen any issues yet, I haven't either. I ran into a code on a Hyundai a year ago and it pointed to the high pressure fuel pump, that's about it. Most of the complaints I hear about is the noise of the system. I imagine most issues are still being handled by dealers because on some cars it's still relatively new. But Audi has been using it for years, haven't seen many issues except for worn followers on the cam. Come to think of it BMW was having some high pressure fuel pump problems with the 535...and some destroyed cams.

If you haven't done a direct injection repair yet I suggest you watch some videos on it or take a small class. The pressures of the systems are very high, it's important to bleed off the system before you start working on it (pressures can reach 2,000 psi during operation). The high pressure fuel pump is very expensive, so be careful not to damage it when you remove it. And the injectors are high voltage (if I remember correctly) and they are probably a pain to remove because they are in the cylinder and head...I'm trying to imagine how bad it'd be to remove with over 100,000 miles on them. Yikes. Very few systems use BOTH the direct and port injection together, although that may change with all the carbon issues on the valves, but that is expensive for manufacturers (and they care more about profit than reliability). Honestly I haven't heard about many problems with the actual systems themselves, more with the carbon buildup on valves than anything else. I used to own a direct injected Lexus...178,000 miles and not one single issue. In fact I've seen cars with 300,000 without issue. pretty surprised to hear the GM injectors failing at low mileage....even more surprised it's not covered under warranty. These systems aren't exactly "new" anymore, every car on the road uses them now.

Sounds like when the driveline is asked to do something/stressed, it makes a worn bearing noise. Could be anything from bearings in the differential, u joint, bearing in the transmission, transfer case, torque converter, flexplate cracked. I don't know, but I'd start with the simple stuff. Check your transmission fluid, transfer case fluid. Differentials. Maybe remove your driveshaft and check the u joints. Check your heat shield too, sometimes when the engine is put under load it can twist enough to cause a heat shield noise that vibrates under the passenger compartment.

Oh ok, so more like driveline. Hmm. U joint sticking a little bit, maybe? Oh wait you said you have a 4" lift...that definitely changes driveline angles and stresses u joints. Maybe put it in neutral and coast when you're experiencing it, see if it goes away. Maybe pull the drive shaft out and check the ball joints. Just some thoughts. More simple type of stuff than condemning the transmission, etc.

So it's coming from the engine? Water pump? Alternator? AC pulley? Rotational noise in the engine usually points to those types of things...the idler pulleys, water pump, alternator, tensioner, anything that spins. Try removing the belt and check for a roughness/bad bearings. I suppose if your truck has over 50,000 miles, any of the above is possible.

I'm pissed at myself for missing it this year...all well, that's what I get for not paying attention. I'm still in the "free" oil change faze (2 freebies from the manufacturer). I did my own oil change at 1,300 miles, then I took it to the dealer at 4,300 miles. I can't stand taking it to the dealer - I sat there for an hour and a half - at some point your own time is worth more than a free oil change. I'll be doing the next one myself using Mobil 1. I'll probably use my last free oil change in the dead of winter when I don't want to crawl under it. I'll be doing 5,000 mile intervals, I'm at 8,000 miles already in three months.

This what I've seen/experienced with the waxy coating on the frame of my 2018. I needed to "touch up some spots" right away after I bought it. There was surface rust from where the coating wore away. I tried a few different products - fluid film was fine to use on the wax (in my opinion). It didn't disturb the existing wax and seemed to adhere to it well. Now some other things I tried?? Not so much. I tried fixing a spot with bar and chain oil and a mixture of graphite - yeah let's just say the wax didn't like it - it kind of evaporated right before my very eyes. I sprayed a rubberized undercoating where I removed the wax, then fluid filmed it. It's been fine ever since (3 months later). I ended up doing a full fluid film treatment to the truck - I considered other brands but Krown wasn't available in my area and I read that NH Oil Undercoating used some petroleum base in their product and it may/may not damage rubber components. So I stayed away from that. I don't expect the fluid film to last much more than 6 months though, so that kind of sucks that I'll have to do it twice a year, but it was fine on the wax and it sticks to everything pretty well. I drove down a dusty road after and the dust kind of "set" all of it up even further.

I tend to just buy whatever is on sale, knowing I'll be dumping it at around 5,000 miles anyway. I do take advantage of the yearly Mobil 1 rebate program they have every spring (although I missed it this year). If I remember ....receive $11 dollars off a five quart jug of Mobil 1 synthetic. So I'd buy six of them at Walmart on sale for $22 a jug ($132) and receive a check from Mobil 1 for $66...ends up being $2.20 a quart for Mobil 1. Unbelievable bargain. And unlike other brands that don't seem to send their rebate checks (hello penzoil), Mobil 1 actually follows through. Make sure to look for it next spring, if you don't already.

I love hearing the high mileage Amsoil stories. Thought about trying it out myself once but I chickened out at 10,000 miles using Mobil 1 Extended Performance. My buddy sells Amsoil 5w30 in his shop. A guy I know worked for Toyota when they were deveoplong their own oil through Mobil 1and going to the 10,000 mile intervals, they were all skeptical about doing those intervals, but the guys from Mobil 1 told them (off the record) that they would feel comfortable going 70,000 using their oil (just toppin up and changing filters). Haha. 70,000 miles using Mobil 1??? Not my cup of tea.

God I hope I'm not sounding like the oil change police, haha. I just like oil talk. Regarding Toyota, yup toyota went to 10,000 mile oil changes on engines that ONLY use 0w20, if the engine can run 0w20, 5w20 and 5w30, it must continue with 5,000 mile oil changes (even if it's using 0w20). Toyota was late to the direct injection party, they use it in their four cylinders now but their very popular 3.5 V6 I believe is still tune port injected (or it just went to direct injection). Also Toyota stays away from turbo charged engines and relies still on naturally aspirated engines (despite Honda going that route). Easier on oil. And as you said, Toyota still requires you to get your fluids checked at 5,000 miles (and to have the oil changed if its considered severe service). But yeah Toyota seems to be doing fine with these extended drains, I've talked to some of their techs and they say the oil still looks good when they take it out. Toyota makes great cars, I'd consider them the most reliable vehicles on the road (I think they passed Honda years ago).

Fuel injection used to be great - and it still is - it just changed dramatically the last five years with direct injection. Now we're blasting fuel right on top of the piston at 600-2000 psi. That stuff is getting into the oil. Carburetor cold starts? Picture an injector running rich right on top of a cold piston and rings that haven't expanded yet.

The timing chains on those Caddys were a real problem, me brother in law was the service manager at a caddy dealer...used to tell me about the timing chains. He told me the only ones that didn't go bad were the caddys from the rental car place down the street. He said they never used the oil life monitor or synthetic, just conventional and 5,000 mile oil changes. Not a single issue. Meanwhile the shop was filled with stretched chains for the customers that used the monitor, went 7,000 plus and used synthetics. I personally don't change my oil at 3,000 miles, I've graduated to the "new school" thought of going 5,000 miles using synthetic. I initially wasn't a fan of the 0w20 oils - I'm still not - but oil viscosity and volatility worries me with the AFM and direct injection systems in this truck. I'm not going to experiment with it just yet (but that may change when the mileage gets high). As for coolant, I generally use OE. I used to hate Dexcool, but I haven't seen an issue with it in a long long time. I've never heard of the coolant you mention, I'll have to look it up. I have seen some interesting coolant...Evans lifetime coolant seems interesting. Ford uses an additive pack with their coolant that needs replenishing with their diesels. Speaking of Ford, they must have 5 different coolants with their cars right now, can't keep up. Hybrid organic acid, organic acid, something else. On and on. I'm a firm believer in distilled water now (if it's not premixed). Honda received the "best coolant award", by some yahoo on YouTube. All I know is I won't be waiting till 100,000 miles to do a coolant service on my truck (I'll live on the wild side and change it at 70,000). Have you ever relined the cylinders in your service truck? 856,000 miles is a lot of service. That's quite a success story. That thing is saving you a fortune.

I understand you don't think techs know what they're talking about regarding fluids, because in all honesty, it's the last thing they care about regarding vehicle repair. Many techs are far past the faze of changing oil, that's for kids coming out of tech school. Instead they're fixing the problems that arise when people neglect changing their oil; they're replacing the timing chains that have stretched, the EGR valves that are clogged (because the oil is being sent down the exhaust), the lifters, the rings, the check engine lights from misfires. When you start taking these things apart, and you see the carbon buildup, the worn components, the sludge (and you know that customer doesn't change their oil because you check the service history), you kind of get biased against some of the things you read on bobs the oil guy, or some of these used oil analysis. I did NOT see these engine problems ten years ago that I am seeing now. Ten years ago everything was port fuel injected and timing belt. Now it's direct injected, timing chain and turbo. The rings got "less friction" to meet the cafe regulations that required these manufacturers to produce fuel efficient vehicles. Then one day we went from putting 5w30 in cars, to 0w20. Just like that. You mention your fleet vehicles, as you know the Detroit 60 12.7 takes 40 quarts of oil. Totally different ballgame. The rpm's probably don't reach 1,300 on the highway. It might even have two oil filters and uses heavy weight synthetic oil. It's made to go a long time without coming in for service (because to take it out of service loses people money). A GM truck takes 8 quarts, and uses a cheap E core filter. The block is aluminum. The valve train uses the oil to uncollapse lifters. It's being asked to flow freely through some pretty tight clearances, quickly. Then it's asked to seal rings that are no longer held against the walls with the same tension as engines 10-15 years ago. An injector is spraying directly in a cylinder at a bare minimum of 600psi, with a maximum of 2000. An engine ten years ago was operating with 50 psi, sprayed outside the cylinder. Now the oil gets a bath in fuel, regularly. It's an issue. No filter stops that. No additive can control it. You take a thin 0w20 oil and make it thinner with fuel. Then the fuel burns off and people send it to Blackstone. Yeah looks great! Go another 2,000 miles next time! I'm not saying to change your oil at 3,000 miles, or 10,000 miles, or 20,000 miles. I'm just saying that there's a reason why GM lowered the mileage on their oil life monitors, why BMW lowered theirs. Why we are seeing more engine failures, ring replacement, valve train issues since the early 80's. It's because technology shifted towards the NUMBER ONE GOAL of fuel economy. Longevity and reliability has temporarily taken a back seat.

Good point, take BMW for instance....someone just mentioned the 15,000 mile BMW oil changes (because it's part of their "free" service). Well I know two BMW service reps, BMW tells them the life expency of their cars is now 100,000 miles. After that? BMW considers them done. They don't care, it's over. They realize their customer base sells them way before that and buys a new one...they don't care about the used car market. BMW engines are failing at a rapid rate. BMW lowered the mileage of their oil change interval simply because the cost to replace engines outweighed the free maintenance they were giving away.

Wait a second...you put 90,000 miles on your truck in a year and four months?? Holy crap! The most I've ever personally seen someone drive is 50,000 a year, and I thought that was nuts. You've got him beat. What are you doing to put that many miles on your truck? And if youre dead set on going 15,000 miles on your oil changes, I'd definitely consider using the Amsoil. And I'd be changing that filter out at 7,000 miles. You should start a thread on your truck - you drive the most of anyone on here - I know I would be interested in hearing how your truck holds up long term - I'm sure others would too. Start a thread, take some pictures...update it once in a while. Tell us how it's doing, etc. Saw a guy do that once on a Lexus forum that drove a lot (not as much as you), it was easily the best thread on that site.

If I remember you're a tech, right? I think you mentioned that before. I'll tell you what I've noticed; every Tech I know changes their oil out at 3,000 miles. EVERY SINGLE ONE. I'm not in the field anymore, I teach automotive, so it's not like I'm talking to 100 different techs a day, but the 20 or so I know personally change their oil at 3,000 miles using synthetic. I was the only one that believed in extended changes, they all thought I was nuts. And what happens?? The rings on my Lexus wore out. So me, this oil nut...this forum reading, telling these guys they're wasting their money dumping synthetic oil at 3,000 miles...ends up wearing out his engine at 160,000 miles. Was it because I was going 7,000-9,000 on oil changes? I don't know, but it sure looks like it. I never beat on the car, it was all highway mileage, I took great care of it, always garaged...but I bought into believing it was a waste to change your oil at 3,000 miles. Honestly I still think 3,000 is too soon...that I can go 5,000, but anything above that gives me the creeps now.

I probably should have made it clear, I don't drive in the left lane cruising at 68 mph. I used to be a regular in the left lane when I drove a car that got 30 mpg highway no matter how I drove, now I'm only in it whenever I have to pass the guy in front of me. But I do find it safer/less hectic over in that left lane, compared to the "slow" lane or middle of the highway. The speed limit on most Massachusetts highways is 65, you'll get run off the road if you drive 65 in Massachusetts. The bare minimum in the fast/passing lane is 75 (even that's not enough).

Excellent post. Do you use your truck for work or is it a commuter? How many miles a week are you driving? I'm averaging around 26 mpg...sometimes 25.5 depending on traffic. I realize the truck's computer isn't accurate but it's what I go by. I set my driving screen to the fuel economy setting, it helps me understand when and how much I can let off the gas pedal and get into V4 mode. And when I can't. I've pretty much got it down to a science now. I'm finding I'm usually averaging 30 plus mpg unless I'm stuck in traffic or going up a hill. I cant beat the cruise control on this truck so I pretty much use it all of the time in the highway - I set it at 67/68 - something where I can kind of "fit in" with the flow of the slower traffic, without causing problems. What I've found is that it's much more risky driving in the slower lanes than the high speed lane. The slower lane has the incoming traffic, which is a pain. And if you go over a lane it's even worse because you're sandwhiched in between two lanes. In the fast lane there's no one to your left and you have less traffic entering from your right (but it's something I've adjusted to). I take full full advantage of this truck's ability to GLIDE. Man can it glide. Going down a hill? This thing builds up so much speed it's ridiculous...never have to touch the gas pedal. And then it glides half way up the other side (and with light throttle you're there). I haven't tried redline products, I'm a bit cheap when it comes to oil. I'll use a full synthetic 0w20 but I change it at 5,000 miles (I don't do extended oil changes). I mean I'll buy whatever's brand name is on sale at Walmart (Mobil, Quaker State, Castrol, pennzoil). I realize they're all group lll synthetics but I've read that with 0w20 oil the manufacturers have to use some group llll just to get it within viscosity specifications. You ever hear of that? I've always read, if you have to chose between 5w20 and 0w20, always pick the 0w20, it's a higher quality oil. My truck only has 7,500 miles on it (it's only two and a half months old), so I haven't tinkered with anything yet. I'm a huge huge maintenance guy though. I'll probably do a drain and fill on the tranny at 20,000. I'll do the transfer case and diffs at 30,000. I'll probably do the coolant at 70,000. I may do brake fluid flushes every couple of years. Thinking about installing a catch can. I have a bed cover I'm putting on next week. I've already done one Fluid Film treatment underneath, I'll be doing another one in November. People say the fluid film destroys the wax on the frame but I've seen zero issues with it (know lots of guys who've had their GM trucks treated). Winters kill trucks around here, it's a serious problem. GM wax starts to flake off after a year (or less), then it just spreads like wildfire. I'm going to try to stay on top of it (we'll see how that goes). If I can slow it down by 50% I'll be pretty happy I guess. I'll be putting 30,000 plus a year on the truck, so it needs to hold up and get me decent fuel mileage. So far it's exceeded my expectations.

Ok. Yeah a front camera would be great. Don’t think I have the option of upgrading it (2018 LT).

I haven't noticed poor quality, and my last vehicle was a Lexus LS460. What's the issue? Not clear? I've driven a lot of new vehicles ranging from Nissan to Hyundai. I don't notice much of a difference between any of them. I will say Nissan gives you several camera angles, which is kind of nice (if you don't consider it distracting). Honda gives you rear and side angles now.

Well I'd say definitely shouldn't have called it a blazer, but think about it...the smaller blazer isn't exactly iconic. So maybe it's no big deal that this thing is called a blazer, unless we're talking about the bigger blazer from the early 80''s, then that's a problem. I actually like it. It looks better than the Ford Escape or Explorer. The interior looks like a Toyota RAV4 (which is a good thing believe it or not). The nose and grill looks aggressive yet not too aggressive (like Honda seems to have fallen in love with). I'm actually shocked at some of these recent vehicles Chevy has put out lately, they look modern, good, have some identity to them (rather than the retreaded bland trash they were putting out ten years ago...remember that Impala and Malibu? Remember the early Equinox? My lord!).

So you're doing simple drain and fills every 22,000 or so for the tranny? Don't think you're going to hurt anything by dong that. Actually I think that's some pretty damn good preventive maintenance, you're essentially removing a portion of the fluid, keeping it replenished and clean, while not doing a complete flush. I've used this technique for many many years with great results. And many others do too. I forget if you mentioned how many miles are on your truck or if you have dropped the pan and changed the filter - depending on the mileage it might be a good idea to get that filter changed out at some point - then continue on with your drain and fills. Just my opinion.

I’ve read it is a decent oil for your typical 5,000 mile oil changes.

I did early on, they came back fine...the usual...you have plenty of active additives left, and wear metals are within specifications...try going another 1,000 miles and check back. Fuel dilution was something i considered. I think direct injection plays a big roll with that in today's engines, that and carbon. It's just a lot of fuel pressure spraying directly down on those pistons and walls. And you throw in the low tension (gas mileage approved) rings and I just don't know?? I have been to classes and lately the "buzz" is watch out for those direct injection engines...those timing chains and that oil consumption. The oil is under a lot of demand and it's getting dirty. You're an Amsoil dealer, you must do extended drains, right? No issues on your truck or anything? You've been hearing good things about extended drains with DI engines? Just curious, I figure Amsoil must have addressed it with their dealers.

It was using a quart every 700-1000 miles. My oil change intervals were 7,000-10,000 miles. I was using TGMO 0w20 and I also used Mobil 1 full synthetic. I was using the factory filters. Excessive blowby was causing oil to enter the intake manifold (a lot of oil). I'd open up the throttle plate and take a look in there and there'd be a puddle of oil just sitting in there. The electrodes in the plugs were badly oil fouled too. Changed to a heavier weight, it didn't help. Compression test was below specs, tried a wet compression test and it went up. Bad rings. Were extended oil changes to blame? I don't know. I believe they sure didn't help.