For background, read these:

http://forums.maxima.org/7th-generat...d-gaskets.html

and

http://forums.maxima.org/7th-generat...warm-idle.html

I recieved a call from the service manager today stating that upon further review of my main bearings, there is significant wear on #1 and #4. He called Nissan and asked how they wish to proceed. Nissan stated they want the engine shipped to them for investigation and they would be sending a new short block for replacement.

I have taken extremely good car of the car... 5000k synthetic oil changes... oil analysis (all stated below average wear)... nothing but Shell premium 93... 90% highway miles... and never abused the car, usually accelerate at about 2500k rpms. I did buy the car used with 18k... it's last mile was just over 41k. Due to my oil analysis results, I have to attribute this to the original owner or maybe I just got a Friday afternoon engine.

I wanted to thank everyone who had input/feedback on the engine knock/head gasket issues. My hopes of this post are that someone will find this information useful in future.

Here are some pics I took at the dealer today

 

 

 

Ok, I'm officially nauseous now...At least it sounds like your dealer is treating you right though.

 

Looks like the bottom of my oven when I was in college ...

Hopefully, it all works out for you in the end.

 

Wow. I'm extremely interested to hear what caused this, or if as you said it was a "friday afternoon job".

 

Can anyone with more knowledge than myself comment on the shape my pistons were in? I'm wondering if they show normal wear/deposits or something else entirely. They don't look good to me, but I'm no expert.

 

I skimmed the background threads but must have missed what year your car is . Good luck with things

 

That's a whole lot of sludge, I have seen motors broken down with 200k that did not have that much sludge.....That Monday and Friday build date thing does hold some merit as workers are rushing for the weekend and just not into from the weekend on Monday. You can have your service advisor give you your build date, both my Max and Z both were built on Wed. just so happen.

 

I second this. It does look like a lot for a relatively low mileage. But I did read you kept on basic maintiance. I'm subbed for what was the ultimate cause of this. I'm glad to read the dealer is taking care of this!

 

Thanks for all the well wishes... I need them!

When you guys say sludge, are you talking about the piston tops? The bottom end looks pretty clean to me. I have never heard of sludge on piston tops (unless burning oil in the combustion chamber) but again, I am no expert.

Yes, like I stated above, I had used oil analysis done and was told I could push the oil to 10k due to the results by Blackstone, I just changed at 5k knowing I'd be good. Used nothing but Pennzoil Ultra. The car was used when bought though... so who knows what the original owner did or did not do!

Someone was wondering what year mine is... 2010 with Feb. 2010 build date.

 

Inside your cylinder heads, in pic #2 and 3.

 

Got the car back today. Seems to be running much better... smoother powerband and no knocking. I'll be evaluating it over the next few days and have to decide if it's time to let her go while I can or keep her now that she's had a heart transplant. I'll be following up with Nissan to try and get the conclusion as to why my original engine failed. If I succeed, I'll post the results.

 

Any updates, pretty sure my 2013 with under 4k miles has the same isssue

 

Every since I bought the car used with 43k back in July i heard the knock, didnt think to much of it.. After reading this post i figure I listen out for it... I started the car this morning and it was fairly quiet.... When I went back out about 15 minutes later there was a light knock on the passenger side

 

Sounds like the # 1 main bearing needs to be replaced

http://forums.maxima.org/7th-generat...-problems.html

 

It came back after about 3 months... continues to get worse. I think they just replace the short block with another faulty short block sitting around in the factory. If 2013's are having this problem, then any "new" short block isn't going to fix the problem.

Since I had damage to #1 and #4 bearing, I know the noise is not just an annoyance and I know all bearings will eventually show wear. I have no confidence in Nissan with the continued reports and the problem reoccurring in my "new" engine. I will be putting the car up for sale in the next week or two.

Good Luck!

 

Wow that sucks what year is your car ? I would bring it back again and look into the lemon law or some settlement with Nissan.

It's your choice but I could never sell a car I know has problems, trade it yes, sell it to a private party, no. With my luck the guy would join this forum, lol

My short block was replaced this week, being we are now over a year since the TSB was released hopefully the new blocks have the correct bearings

 

It's a 2010. After a CVT issue (valve body replacement) and a new engine, I'm done with it. I bought it used, so the lemon law is out.

I might trade it if I get a decent price... if not, I won't have a problem with selling it. It drives fine. If something goes wrong it will be over 100,000 on the odometer (engine replaced at ~45,000).

I have no idea what I will get next though...

 

Good luck, mine has 3800 miles and 8 ( business) shop days , 30 days within 2 years activates the lemon law in MN


If Nissan is still shipping locks with the wrong bearing over a year after the TSB that's just sad. Since Nissan actually sent a rep ( found out today) to see and test the car before ordering the block I'm hoping they are taking the problem seriously.

If I was you I would take it back and make them do it again

 

In some engines a wearing wristpin can make a knocking noise. Engines with this problem in many cases during warm up the sound calms down because with the pin being made of steel expands within the AULM piston hole. with the cold weather coming these noises are more apparent. A easy way to tell a rod knock VS noisy wristpins is to put the car in gear and power brake it. If the noise gets louder and changes tone then its a rod knocking. If the noise stays steady and the tone don't change its a wristpin. I drove some cars thousands of miles with noisy pins. Remember the old Chrysler 2.2 & 2.5 K cars? 75% of them had very noisy wristpins. From what I can see your pistons look alright.

 

Looked on the internet just now in ref to you year & model and many have this issue. Watched a few videos .These engines wont blow up because if it were rod bearing these cars would have blown long ago. Alum & Steel expand at different rates under heat. And Alum don't expand as much as steel does. Todays engine oils and much thinner like 5W-30 VS 10w-30 & 10W-40. The lower weight oils have a much higher boiling point and are less susceptible to brake down during time insuring that the parts will last longer. Tolerances ( space ) between engine parts need to be manufactured much closer. Brake fluid is very thin and is an oil product but has a very high pointing point and brakes get very hot. The cure would be to raise the engines temp a little expanding the parts some more and a slightly higher weight oil, both of these thing would take up so slack. more annoying then anything but will not put you on the side of the road.

 

88Se, the noise is not there cold, it only comes after warmup.

If it wasn't a serious issue I doubt Nissan would be replacing blocks at 3800 miles or doing the main bearing per a TSB

From the TSB which calls for a larger # 1 bearing

NOTE: If an engine has a knock noise from the # 1 main bearing (confirmed by the above symptoms), the noise will not be eliminated by changing the oil grade or type

 

After warm up than the oil is not thick enough to bridge the gap of the wrist pins. If that engine takes 5W30 then its 30w cold then drops to 5 when warm. Its been my experience with main bearing wearing out they don't make noise. BUT when they do wear out the oil pressure drops and result may be other parts like the wristpins not getting enough oil along with other parts. That's weird your mains on two journals took a crap. Sure Nissan will take a very good look at your short block. they are nice cars.

 

Oh my. Been looking at you block for a few minutes now. thinking about its design. That forward Cyl is very dirty. When a bearing wears down a good bit of oil pressure runs right out of the sides of them. And that cyl suffered oil loss. There is a tiny hole in the rod that points at the bottom of the Cyl wall and squirts oil supplying the wrist pin some along with the rings. Lack of oil on the rings means lack of full compression. The dirt left behind is due to un burnet fuel. This is my opinion. That design engine is all Alum. You typical engine design has main bearing caps rather then what this one looks to me I would call a sandwich design. The crankshaft is Steel. The steel expands less had it backwards then Alum. The Alum cools faster as well. The crankshaft will be expanded longer during cooling then the Alum. In this design the alum would be stretched out. That plate section should be made of steel that Alum blanket sandwich does not work for me. Don't think Nissan messed up on bearing size think it wore out due to its design. But maybe they did. That's not counting the force generated on that plate, not only heat expansion, force straight down. Hard to say just pondering don't like to see this happen to anybody. Be nice if its just a handful of defective parts that had a effect on a few of this model Maxima.

 

It's not my block in this thread, my car has 3800 miles the one you are looking at has about 50K miles, the TSB says the bearing is too small but in my case Nissan is sending a new block HOPEFULLY with the correct sized bearing

When you put the car in gear the noise goes away in lower mileage cars but not in higher mileage ( 15K ) it seems.

People have had the bearing replaced per the TSB and the noise goes way, the TSB is not doing anything besides putting in a larger bearing.

Nissan is not replacing blocks and bearings because they feel like it, the bearings aren't wearing out, they are the wrong size out of the factory it seems unless something is seriously wrong causing the bearings to wear at 3800 miles and if that is the case replacing the bearing would be a very temporary fix


You can signup and below and download TSB NTB12-071 if you wish to see what they are doing to fix the issue if they don't ship a new bloclk

http://x.nissanhelp.com/forums/Knowledgebase/links/160



IF YOU CONFIRM



A knock noise coming from the # 1 crankshaft main bearing:


NOTE: Refer to No.1 Main Bearing Knock Noise Confirmation on the next page.



ACTION


1. Remove the # 1 main bearing (upper and lower halves), per the Service Procedure in this bulletin.



2. Select and install a new # 1 main bearing that is one grade higher (thicker) than the one removed.

 

Yeah that sure is better then all of them going south. As many parts that are made and go into cars something has to go wrong sometimes. One wrong thing can though things out of wack.

 

It's effecting a lot more cars than Nissan is letting on. As an owner I'm glad because this could kill resale value but on the other hand I never buy one.

The other thread on this subject is a week old and we have several people with the same issue plus 6 confirmed in my PM, by confirmed I mean the dealer is saying something is wrong, others haven't had the car looked at yet.


What concerns me is the guy who started this thread had his block replaced and the bearing knock returned meaning as recently as 6 months ago and 6 months AFTER the TSB was released Nissan was still shipping out blocks with the wrong size bearing

 

I ponder type and think out loud. Nissan develops a nice product with much thought. Maybe the left hand font know what the right is doing. Have to get up to speed. Sure replacement of that bearing there is time involved. On some recalls or campaigns they develop kits and give them their own part number. Assures that the Tech has what they need to do the whole job. Gaskets and what not with the correct bearing.

 

Seems it's not always the same sized bearing thus use one size larger is the fix, and it's not always replaced sometime a new Block is ordered. You should Read the TSB. I also don't believe Nissan is doing this just to fix a noise, they know it's going to fail eventually


NOTE: If color cannot be determined, refer to page 48.
77. Choose the grade for the new #1 main bearing as follows:



Figure 61
b. Select a new main bearing that is one full grade above the bearing that was removed.


Examples: If Yellow was removed, which is grade 3; select grade 4 (Blue) for installation.

If Blue/Yellow was removed, which is grade 34; select grade 45 (pink/blue) for installation. # 1 MAIN BEARING GRADE
GRADE COLOR
PART NUMBER
0
Black
12207-31U00
½ grade: 01
Upper Half – Brown
12207-AG000
Lower Half – Black
1
Brown
12207-31U01
½ grade: 12
Upper Half – Green
12207-AG001
Lower Half – Brown
2
Green
12207-31U02
½ grade: 23
Upper Half – Yellow
12207-AG002
Lower Half – Green
3
Yellow
12207-31U03
½ grade: 34
Upper Half – Blue
12207-AG003
Lower Half – Yellow
4
Blue
12207-31U04
½ grade: 45
Upper Half – Pink
12207-AG004
Lower Half – Blue
5
Pink
12207-31U05
½ grade: 56
Upper Half – Purple
12207-AG005
Lower Half – Pink
6
Purple
12207-31U06
½ grade: 67
Upper Half – White
12207-AG006
Lower Half – Purple
7
White
12207

 

Just to be clear for me ( and others who may see this thread later) you had your block replaced in 3/2013 and around June of 2013 the knock returned, is that correct ?

Since 3/13 is 6 months after the TSB came out does anyone know if you can find out when the block was assembled ?

 

What kind of vibration dampener does that engine have? Back in the day on an old ford my front main got trashed because I drove around too long with a worn one. Maybe that engine needs something like that or a modified one. Could not see what kind of setup is on the particular engine. Instead of the jackhammering a good rubber dampener may prevent from the start. The bearing are different sizes because they are adjusted to the wear of the crank journal, just a thought.

 

I'm sure Nissan knows what's going on and decided the block or bearing replacement was best

Not sure what you mean about the bearing sizes, my point was since they aren't saying replace "x" size bearing with "x" size bearing and instead want the next larger size used makes me think these motors don't all have the same bearing size

 

Yes... short block replaced 3/2013 and knock came back June 2013.

Also, I want to make clear that the mechanic took my engine apart and said there was DAMAGE to #1 and #4 bearings. This means the noise is not a harmless noise... damage IS occuring. It is only a matter of time before people start having engine failures... probably around 100,000 miles IMO.

I also would hesitate to only have the bearing replacement TSB done. The noise may be fixed, but I guarantee you damage has occurred to at least one other bearing and the TSB says nothing about checking the integrity of the other bearings.

I was thinking I might take it in again, but I am just SO tired of dealing with Nissan. I'm thinking a V6 Accord is in my future.

 

Did that short block come directly from Nissan in March ? no possible way the dealer ( or another local dealer) had that block in stock meaning it was made pre TSB ?


Since Nissan wanted to see the motor I'm surprised they let ( and the dealer paid the mechanic) to break down the old block to look for damage, engineers are funny like that, they don't want other people touching things.


Nissan has been nothing less than fantastic so far to deal with for me. I let the dealer hear the noise, showed them the TSB and it was there idea to get the new block the next day, I expected the bearing to be replaced not a new block.

From talking to Nissan I bet they would love to see your block again as he told me all the possible defective short blocks were taken off the shelves in late 2012 and broken down as I mentioned I was worried ( citing you as an example) that the bearing knock might return. My new block was assembled 8/2013. Nissan seems to be following this repair and documenting everything as he knew the info right away.

As far as compensation, nothing is set in stone but I asked for the Gold Preferred 8 year warranty and he said he would do everything possible to make it happen

If nothing else getting another block lets you sell the car with a clear conscience as it will be good, for a while at least, good luck

 

Yes, it came directly from the Decherd, TN plant. I live about 2 hours away so it came next day.

Originally, the mechanic tore the engine down to replace the head gaskets and perform the bearing TSB. That is when he discovered the damage and called Nissan. Nissan then requested the motor be shipped for investigation.

I didn't ask for compensation though. I'll call Nissan again and ask if they can tell me the build date of my block and to request the Gold Preferred 8 yr warranty.

 

The way they diagnosed my engine was a bit odd, it's on the buyer beware thread

If you score a 8 year warranty on a car with 50K miles you didn't buy new you made out big time !

I haven't got the final word on my warranty yet but when I told her I have owned Nissan Products since the 90's and actually traded an Infiniti for my current Maxima she noted it and told me they would take the loyalty issue into account, I'm sure they are checking to make sure I did trade that car in

 

I provided all engine block numbers/letters/stamps to my dealership to find out the new short block build date... they responded that they have no way to trace the engine block and provide a build date.

I think I am officially being dismissed by Nissan.

I believe they gave me a replacement short block that was of the same build quality as the original (bad bearings)... Being I came in 5 months after the TSB, I think they had remaining faulty engines stocked, gave me a new, yet faulty (older), short block... and hoped it would shut me up for the next 10,000 miles until my engine warranty ran out.

Thank you, Nissan.

 

Wouldn't your new short block be covered by a new engine 6yr 60K warranty?

 

The new short block is covered under the original warranty only. That is 6yr 60k miles from purchase date. The warranty does not start over with a new short block. I have about 50,000 miles on the engine now... so about 10,000 miles until I am on my own.

The dealer refuses to admit there is a problem even though the noise is the same noise as the original engine. They first stated they didn't hear anything... then when I demanded to go to the service bay and listen with the tech, they then said they heard a noise but it was just valvetrain noise. I argued that valvetrain noise is not heard on the bottom of the engine and is not a distinctive knock. The funny thing is the noise is the same noise that warranted replacing the original engine, yet now it is "normal." It is even on the passenger side of the engine block near the bottom... right where the #1 bearing is.

I need to request a Nissan engineer to come listen to it, but I just don't have the time in the next few weeks to go fight with them. I was going to trade the car in but cannot afford to do so. I'll put up a fight in a few weeks an report back.