I've posted on here before, and thought I'd keep the information coming about the good and bad of these vehicles. I am back in the dealership at 126,000 miles, with some NASTY internal engine noises.

Some backstory; 35,000 miles ago (I think, it's been awhile really) I had the AFM motor problem; the small screen under the oil pressure sender plugged up and the indicated oil pressure dropped to nil. Had it towed, and the dealer replaced the screen under warranty. After that the engine would occasionally let out a HUGE cloud of smoke on startup; blue, stinks-like-oil smoke cloud that was triple the size of the Yukon.

15,000 miles ago (give or take) the dealership agreed to do some major engine work to fix the intermittent smoking issue on startup. The diagnosis was that there were some bad valve stem seals and that a couple of lifters were going flat and clattering on startup worse than they were supposed to. They replaced all 16 lifters, rebuilt the heads, valves, and basically the whole top end of the motor. New little screen under the oil pressure sender, and it was working well up till a week ago.

Now there are some terrible valvetrain noises from the top end of the motor; they tear into it and learn that the camshaft has pitting/flaking/extreme wear. Of note is that I've always been up to date on oil changes, and have only run synthetic oil and change it somewhere between 6 and 7500 miles.


The dealer wants to split the bill 50/50 with me for the camshaft, because it is not the same parts they worked on last time and I'm out of the normal warranty. I appreciate the offer as I realize that they are out of the warranty period, but really I think they should handle the repair completely. There isn't a closer relationship between parts than lifters and a camshaft, and if the lifters were not installed properly this damage would occur. Not to mention, really for a 2008 engine that sees almost exclusively highway mileage a cam rounding out is very out of the ordinary. I've had vehicles that I've beaten into the ground in my younger years that saw twice the mileage and fewer problems. If this were the first occurrence of this problem I'd take the 50/50 offer but they've had 2 opportunities previously to get it right and they've failed me.

The next problem is that they are not willing to drop the oil pan to see what has been pumping around the inside of the motor. If metal shavings are in the oil they will be in the bottom of the engine, where they will just be circulated into all the bearings and other places that are not so fond of metal particulate. I'd like them to check out the lower end bearings while they're at it, but really that depends on how much junk is in the oil pan.

What's more is that I called GM customer service on Thursday and was given the run-around by the first person in the general customer service pool, then finally was transferred to my district specialist. When they did not prove to be helpful, I asked to move up the ladder and the call-taker's manager was conveniently 'Out of the office till tomorrow, can I have them call you back in then?' I said yes, and it's been 3 days. If you're not going to advance it tell me, don't lie to me about your boss being gone at 1:30 on a Thursday.

I love this Yukon and don't want to give it up, and really what bothers me is that this has little to do with the Hybrid aspect; it's been internal engine problems that are common to the AFM motors. That means that if I'm going to give up on this Yukon I'm going to be giving up on anything with the AFM engine in it. GM has been good to me with fixing these problems, but when it takes 3 times tearing the engine down I've about had enough.

 

I would only consider 50/50 on a new engine. This one has had major surgery too many times.

 

That's about where I'm at, I'm tired of seeing this in the shop for stuff that should have been handled when it happened. No more reactive repairs, lets get some proactive work to make the thing right again. I think they want to avoid pulling the whole engine, but at this point how do they justify the amount of work they've done without yanking it and checking it over? Guess that will be up to GM, I've sent GM customer service a PM on here already and will await their response. Really sucks to be doing this over the holidays, and I'm supposed to be moving next weekend too. When it rains it pours!

 

See post #4,

http://www.gminsidenews.com/forums/f...roblem-106584/

http://forums.iboats.com/dockside-ch...gm-635011.html

 

I know all about the AFM motor troubles, this started out as one of those issues but has long since escalated to problems with related parts and issues with GM making a problem right.

 

Thought I'd give an update to the resolution of my issues:

Considering that major engine work had been done less than 15k ago, the shop decided to do the major surgery; replacement cam, replacement of bad lifters, replaced vvt actuator that was out of spec, dropped oil pan to clean it out(on my insistence; they didn't want to do that but it'd be stupid to leave all the metal from a cam floating around in the bottom of the engine getting churned up by the oil.), and gaskets all the way up. They threw in a synthetic oil change after 500 miles of driving with the new parts to make me feel better too. Total tab would have been in the $6500 range, they got it down to essentially $850 plus GM customer service botched my ticket and didn't call me back for a week so they threw in a $100 service voucher.

Funny thing is that I've had co-workers give me grief about the hybrid having so many big engine problems; NONE of these have had anything to do with the hybrid! It's all been AFM related, the hybrid has been working perfectly. (Knock on wood...)

PM me if anyone else has been having engine troubles, I can get you contact info for the dealer I've used; very happy with them given what they could have charged me.

 

what oil and fuel were you using before this problem came up? I have only used mobil 1 5w/30 EP synthetic since break-in oil and have used only 93 octane for better gas mileage and have no problems so far at 154k miles.

 

I bought the truck with 85K miles on it, so up to that point I have no idea but I've normally used my dealers GM branded full synthetic oil. I think its a Castrol variant. My first trouble was at 98K miles, when the oil pressure sensor screen plugged up and starved the lifters. I figure if the engine calls for GM spec oil, I'll put synthetic GM spec in there.

 

the plugged oil screen is probably due to the use of Dino oil. the LFA engine requires Mobil 1 full synthetic as the engine oil cap would indicate. buying a used vehicle has it's drawback esp for a vehicle this advanced. I hope you did buy warranty.

 

Just for historical info, my 08 Yukon Hybrid at 62K started running rough. Dealer replaced entire engine without any hesitation. Sorry, don't know what the actual problem was. Now have 85K and fortunately no issues.