2010+ Buick Lacrosse Engine and Powertrain Problems

gberpa

You may have something re: delay. My dealer's SM posted elsewhere and several months ago a recommended 5-6k miles for the LaCrosse. I just peeled off their "reminder" sticker which shows 3K. Not sure if this was just an "automatic" by the tech or a change..will ask on Thurs when i stop by for my free birthday car wash/wax.

Re: jet engines, are those for commercial ones? Mil specs, which are usually tough don't preclude dino..see:
http://www.qclubricants.com/milprf6081.htm

gberpa

I had my 2011 CVS in to the dealer today for a complimentary (birthday month!) wash and wax and discussed Banto's comments re: the EnclaveTSB. I also noted to him, after my recent oil change, the sticker the tech put on windshield which said to bring it back in 3K miles. I questioned whether he changed his view of a recommended oil change interval of 5-6k miles on the LaCrosse. On the last point, he said he hadn't changed his view but a lot of long-term customers might get uncomfortable seeing a longer interval. He is going to shift the techs to sticker a longer interval. There is no OLM TSB for the LaCrosse.

The issue, as he explains it, for the Enclave was that a lot of folks were following the extended change interval per the OLM AND they were not monitoring oil level during the longer intervals (stupid, I'd say). As there could be a loss of maybe 1 qt/5,000 miles, and say 2-3 qts over 10-15k miles for those following the OLM exactly, that low oil level and oil flow surges could/did result in timing chain stretching for some. So, Buick decided to change the OLM programming for the Enclave.

My oil level didn't budge over the first 4100 miles but your results may vary. So, for those pushing the OLM projections to the limit- check you oil levels. Also, E-net rider posting here found high gasoline/light ends levels in his 5800 mile old oil which he sent in for analysis. This means the effective resistance to wear (viscosity) could be even lower for our engines at longer change intervals.

crankeee

Totally agree with checking your own oil level periodically IN ADDITION to watching the OLM per prior posts. If the oil is down 2 quarts out of 5.5 and the OLM says 60% oil life remains, you have a major engine protection problem IMO if you do not add or change oil.. Also newer DI engines dump more gas into oil, as previously posted, for various reasons, resulting in need for sooner changes due to dilution- oil level may not go down but viscosity does, as you comment on. Dealer putting on a sticker with 3000 mile oil change supports both of the preceding comments; 1) don't rely on the OLM soley for oil change interval and 2) change the oil on your own schedule prior to gas dilution or loss of viscosity resulting in timing chain or other mechanical failure. $30 to protect your $5-$8000 engine is a no brainer decision for the dealer and should be for the owner!

e_net_rider

Thank you for the quote from dealership. That is a definite "Aha!" moment.
The part about oil surges and timing chain.
The loud steel to steel bang upon start coincides with what I have been wondering, believing to be from oil drain down between runs.
If it made the loud bang, shutting down and restarting never repeated the sound. Thus it would take time for the oil to drain down again and as I posted some time ago, my factory PF48 was missing its anti-drain back valve.
If you have a vehicle that has not yet had oil changed, I'd definitely be concerned and save that filter. There is no knowing how often one of these slips by.
As to those who had problem fixed by changing exhaust, you may have had a different problem. What I was hearing, at no point did the sound make sense as coming from something in the exhaust. It was too loud and too defined as something heavy, steel against steel. Like maybe a 3 to 5 # engineers hammer against a large anvil.
BTW, I do get a sound in the exhaust upon start occasionally. It is the sort of sound I would expect from exhaust pipes, catalytic convertor, etc.

e_net_rider

Book suggests checking oil level at every fill of gas. That seems a bit of overkill to the point that they should have included a low-level sensor as they did with some others.
You might check it 50 times showing no use, then something catastropic happens and it loses all oil on one tank.
I can't help wondering if dexos contains some secret ingredient to deal with excess gasoline?
There is a consensus that this engine with DI & VVT has been showing high gasoline content in UOA. And possibly tied to timing chain issues. I have not explored the siblings of this engine or any other that employ both DI & VVT, so I do not know how widespread the issue is or if issues are related to these technologies.
Because of results of UOA, many high readings with the lab calling attention to high gasoline, I will continue to test and monitor, probably avoid going below 25% or more than 5-6K miles between changes. To date I have seen absolutely no oil use, period! Even though GM is tying low oil to timing chain issues, it may extend to not using any oil but being diluted by gasoline. How bad is gasoline? My Dad runs many engines on the farm. Older ones often being more rebuildable than some newer ones and not as fussy as those with newer technologies. One thing he has used over the years are John Deere Gators. His biggest problem was because he did a lot of short runs, not allowing engine to be thoroughly warmed and burn off fuel, the gasoline engines all failed quickly and in one case right at one year. He never had issue with the diesel version because the fuel is like a very fine grade of oil. One of my sisters had 79 T-Bird w/400M that only lasted 27K because of gasoline issues. Most days it went less than 2 miles one way to work, school, or grocery. Under such extremes she probably should have been changing every 500miles or 2 months and for my Dad every 10 hours on gasoline Gator.
A sure killer of a motor if not caught in short time was the failing of mechanical fuel pump diaphram. They often leaked into the engine without external clues. A couple of basic rules for gasoline, never use as a solvent because of danger, and certainly never use on bearings because it will start rust which destroys the bearing, eventually. Sound like you want it in your motor oil? It will cause your bearings to wear out and destroy seals. It will also gum up lifters, valve seals, and rings.
I think GM owes us the truth about the gasoline, timing chains, etc. Do we need to change oil every 2K/2mo. for a long lasting engine? Or is that overkill? These bits and pieces, rumors, are not satisfactory. I do not like the idea of being the 1 in 1000, or whatever numbers game they may be using, that results in a bad vehicle.

crankeee

I also lean towards more frequent oil changes - 5000 miles max until the gasoline issue is clearer. Also the issue of added ethanol is coming up more. Damage to rubber and synthetic fuel lines so who knows?
Small engines appear to be obviously affected and Stihl, Toro, Honda warn against ethanol damaging engines. The latest proposal by the feds to increase ethanol to 20% caused a reaction by car makers (FINALLY!).
Timing chains on DOHC engines is a pretty new subject since the domestics lagged the offshore makers by 20 years on that technology IMO. The Japanese used belts rather than chains for 20+ years but replacement was VERY important and expensive. We will see if the long term durability of the newer GM, Ford engines lives up to the old Honda- Toyota engines that had VVT,DI and DOHC years ago.
Good luck to us all.

e_net_rider

I don't believe there has been issues with DOHC. GM has had the Aurora/Northstar for a lot of years. I'm thinking the Mercury built Vette engine is also. Ford has the 4.6L which started in Town Cars and spread to trucks and 'Stangs.
Automakers have made statements about E85, high alcohol content, claiming they can't make engines last using it. I find this a bit strange since alcohol burns cleaner than gasoline. Is it Brazil that has been using it in lieu of gasoline for probably close to 50 years?

bwia

Call me compulsive but I change my oil 4 times a year at the beginning of each season: spring, summer, winter and fall. Since I do mostly city/suburban driving I believe these are considered extreme driving conditions and therefore require more frequent oil changes. This prescription has served me well over the years and I've never had an oil related problem, even driving the sludge-prone Avalon.

crankeee

Frequent (3000 mile) changes seems to be an abundance of caution, but that is what we have done for 40+ years. GM has used overhead valve engines for years but dual overhead cam all aluminum is a more recent model. The engineering for these "lighter" and "cheaper to make" engines may or may not allow for extended oil change intervals- only time will tell. We had a '90 300ZX that needed that schedule due to increased gas dumping into the oil, esp. when the cold start valve acted up (like the old choke) and incresed the mixture and idle speed. Your plan seems cheap relative to the downside of major engine problem!

e_net_rider

The subject of engine shaking around 1500RPM, plus & minus a couple of hundred RPM is resurfacing it appears.
I have not received a satisfactory answer as to why, just that other new ones do it also.
GM must think we are stupid and can't understand a real explanation.
For me it is of concern in many ways but in part because that range is so close to cruise RPM at a number of lower speeds. Unless they are actually shutting fuel off to some cylinders, it would be indicative of a poor burn.
BTW, I'm now seeing a long hesitation when I need to suddenly accelerate.

crankeee

Rider: Is shaking happening at idle or on the road under load? The DOHC higher revving engines DO NOT like to be lugged or loaded at relatively low RPM's. couple that with the newer 6-speed being programmed with a preference for economy (quick to upshift - slow to downshift) and it is easy to lug the engine. The old GM aluminum 4.1L in Cadillacs was famous for this since it was grossly underpowered relative to the vehicles obesity and was very easy to lug. Higher revs keeps the family happy in one man's opinion.

e_net_rider

At idle, but I wonder if connected to the amount the speed drops if accelerator is held steady when approaching an incline then going over. There is an arched bridge I frequently cross and speed changes about 20 MPH in the 45MPH zone.
At 45, you are not in 6th gear.
I thought one of the advantages of VVT was a flatter torque curve. I wish I had the curves for torque & HP, just to see what they look like at speeds around 1800 -2500 RPM.
I think the engine you mention was TBI and most engines of that time did not put out near the power of newer versions. My son-in-law has a Tahoe which I believe has the 4.1 Vortec. Nothing under powered about it according to him. He claims if you put foot in, it will put you in the seat. He uses it to tow and when he goes camping it gets a 19' boot loaded up with lots of camping & other gear. It does not bog at all when he gets into the big hills.
GM engines have traditionally been a long stroke giving more torque at lower RPM. GM has had a couple of engines that were down stroked models of others and those typically like more RPM. The 327 downstroked to a 302. The 4.6L Aurora downstroked to 4.0L.
I had the 4.0L with 4 speed tranny. It would be in OD at 45 MPH and I typically only saw about a 5 MPH or less drop going up that bridge.

crankeee

Rough idle would not be the same as the lugging that occurs with higher revving engines. Motor Trend commented that on some of the newer DOHC/DI engines the HP rating was quoted at much higher RPM's than SOHC configured engines. I agree with the comment on other GM engines. We have an older 3.8L with 4-speed AT and it flies up the grades at 70-80 with no lugging or downshifts and the RPM's are as low as our 2010 CXL 3.0L. The 3.0L just needs to have the revs over 2000 or so to keep from lugging down on big grades. The Wheeling Hill in WV is easy to climb at 80 in the Lacrosse but at 65 it keeps searching for a gear up & down so I use the manual shift to lock it into a lower gear if 80 can not be maintained.
Just a different operating car that requires relearning operating tricks.

imidazol97

>I wish I had the curves for torque & HP,

Are you wanting graphs for the 3.6?

e_net_rider

True, but most engines that would display the first have a big chance of displaying the latter.
You make it sound like this would be better mated to a CVT transmission.
I am going to play a bit and try to figure how wide a range I'm seeing the big delay when I want acceleration.

e_net_rider

Yes. Thank you.
Wow, the torque curve is far flatter than I imagined possible with the addition of VVT. According to old rule I had run across, engine peak efficiency occurs around maximum torque. Those older engine curves had quite a big change and this one is near flat.

imidazol97

The great 3800 has a relatively flat torque graph, but it does taper down at higher RPM.

This is the 3800 version that was in the Lucerne. I can't find a graph of the leSabre/ParkAV version earlier.

crankeee

Exactly! The flatter curve for the older 3.8L clearly shows that the same torgue is not generated until ~2500 RPM's on the newer DOHC higher revving engine. Below 2500 the torgue and HP is much lower. Same point as posted before - the newer DOHC/VVT/DI higher RPM engine needs to be at higher RPM to get same or better driving performance .
Great visual portrayal of the different performance.
Thanks!

crankeee

Not at all. The new 6-speed universal AT in the Lacrosse and other cars is a good match with higher revving DOHC engines. Lower torgue/HP in lower RPM range requires more gears and the higher final drive with top gear engaged allows for great highway mileage & good driveability - just have to keep those revs up. The torgue/HP graphs really show the story - great post by imidazol97.

imidazol97

It looks to me, that the torque of the 3.6 vvtdi is equal or higher than the torquey 3800 from 1000 to 2500. But my point in posting the rather torque-high 3800 was that its high torque with a properly geared 4-speed and proper final gearing gave a good performing motor for its car type--which was the leSabre/ParkAV and also the Regals.

In the new LaCrosse, much depends on the match of the engine torque to the final and transmission gearing. And also now there's even more pressure for high gas mileage.

I haven't followed the discussion closely on the engines and torque so I probably am off on a different point than the actual topic, so I'll just keep reading.

gberpa

I don't quite follow your drift. If the torque vs RPM is relatively flat, why do you have to keep the RPMs up?. My understanding is that its the torque- not HP per se- that gives you the 'oomph' or acceleration. My 2002 Hyundai XG350L had modest HP- I think 195- but had very good acceleration relative to peers due to high torque and a relatively flat curve.

For me and at its current mileage (~4800) and state, my CXS has a good balance of auto shifts and mileage. Even when it downshifts on mild uphill climbs, my speed doesn't drop.

BTW, last evening in torrential rains and some minor flooding on roads, the traction control/stabilitrak and 18" Michelins worked great and I felt very secure.

crankeee

crankeee

Comment referred to torgue curve on older 3.8L as being flat not the newer higher revving DOHC/VVT/DDI engines that require more RPM's to produce same torgue or HP. Need to keep the revs up like a motorcycle or small engine sports car. Older large blocks were so oversized vs. the car weight you could hardly lug it down - not so with smaller higher revving engines.

e_net_rider

Are you saying that you got lights for traction?
If not, then the Michelins were doing the job.

e_net_rider

Not sure what version of a 3.8 these charts are for such as newest called 3.9 or much older that I think began as TBI, throttle body injection.
It is impossible to guess whether the latest additions to engines is for pollution or mileage or some combination of.
Comparing those two charts, compare torque or HP for an equal RPM of both engines. It looks like the 3.6L is higher in all cases.
Traveling a steady speed, Lacrosse with 6 speed & smaller body for wind resistance compared to Lucernne with 4 speed, it would seem that there would be more than just 1 MPG difference for highway. That is what I remember window stickers to show anyway.
Overlay curves of fuel consumption for those graphs might reveal something, but not hopeful at this point.

gberpa

You know, I'm not sure about the TC/Trak lights coming on but I don't think so. I was focused on paying attention to the road and avoiding oncoming glare. I heard the tire/water/road sound you often do before a possible hydroplaning episode (if you're at high enough speed which I wasn't) but the car held the steering line very well so I guess it was mostly the tires.

imidazol97

>The flatter curve for the older 3.8L

The graph I showed was not for the 3.8L. It is the 3800 which is vastly changed from the 3.8s of the 80s.

The particular graph is of the later version that was in the Lucerne. I believe the earlier version had slightly better horsepower and/or torque rating.

imidazol97

>Not sure what version of a 3.8 these charts are for such as newest called 3.9 or much older that I think began as TBI, throttle body injection.

I am nnot clear on what you mean here. The 3800s were not related to the 3.9L.

The chart was for the 3800 in the Lucerne, the last iteration of the engine. It had sequential port fuel injection, AIUI.

e_net_rider

My bad. I did not realize these were totally different engines. If I understand you correctly, you are saying this is like the old days of Ford where they had three versions of the 351?
I do know that whatever Buick was putting in those older vehicles, 90's, must be one tough engine. There are a lot of them on the road yet.

e_net_rider

I mentioned a few time the factory PF48 that is missing the anti-drainback valve. I told a few at the dealership. I remembered to take it with me when I picked up my car yesterday. The service bay manager was the first to query what I had. I told him and then led him to the parts counter where we asked to see a new PF48. I showed the difference to him and the parts guy at which time the manager of service walked up and he looked to. All three were jaw dropped shaking heads in disbelief. Of course they could not comment on GM since that would be like talking bad about your boss. Now close to 3000 miles since I changed it and oil, and I have not heard that horribly loud hammer on anvil sound from the very front, at start, even once. I do occasionally get the exhaust pipe sound. And wonder what damage was done to the VVT system.

BTW, the battery that went dead in less than three months and was replaced. It has been replaced again. It was leaking acid and developed a corrosion spot where it was dripping.
Every day I am more and less impressed.

crankeee

rider: I bought PF48 at Auto parts store and the drain anti drain valve is in the bottom per prior internet posts.
Also found out tha it takes these cars a VERY long time to drain down for a good oil level check, which I guess is the idea. I have read no posts of oil consumption on the 3.0/3.6L family in current posts. Once the consumer stopped relying totally on the oil life monitor and started to check the dipstick. DUH! Ours has the 3.0 that is in Cadillac SRX models and good motor so far.

e_net_rider

If you are checking for the valve, look into the bottom holes, except the big threaded one in the center. You will see black rubber and that is the seal. On my bad one, no seal, just metal from likely the end of the filter cartridge.
Mine certainly did not take much time to drain down during the time that filter was on. I'd check very frequently, even after just filling gas the stick would be up.