PSA: Moly vs Piston Slap - Nissan

[legatinho]

Hi All,

I have a Nissan Versa with the MR18DE engine. It is quite famous for having early failures due to piston slap, and I've got my short block replaced under warranty due to it.

Anyways, my engine started making the piston slap noise again (only when cold and under load), the only change was that I switched to synthetic (I was using Valvoline conventional before).

Checking the oil composition, I noticed the main difference was sodium and moly content (valvoline has sodium and no moly).

So, as an experiment, I did the following:

1 - Removed the synthetic (Mobil 1) and re-filled with Valvoline conventional
2 - Noted that the piston slap noise is gone (it didn't go away right away, took a couple of drives)
3 - Added a bottle of MOS2 to valvoline oil - piston slap noise came back

So, if you have one of these [censored] Nissan engines that are prone to slapping, I'd recommend staying away from MOS2, and Valvoline seems to be the better suited oil.

The block only got 5k km on it, and hopefully I have not caused any permanent damage by using MOS2 on it.

 

[demarpaint]

I doubt you did the engine any harm. Why didn't you just go back to the dealer with it? With a spec'd oil, no additives, and proper level they'd have no ammo to use against you.

 

[aquariuscsm]

Originally Posted By: legatinho
Added a bottle of MOS2


That was your mistake. Nissan specifies per fsm to never use oil additives.

 

[legatinho]

Just to clarify, the engine is not slapping atm, as I once again removed the "contaminated" Valvoline oil with MOS2 and poured a fresh bottle. I ran less than 50km on that oil.

I'm just leaving this here as reference in case someone experiences slapping noises with nissan engines, it's worth a shot to switch to an oil with no moly (like Valvoline).

 

[volodymyr]

legatinho,

Originally Posted By: legatinho

I have a Nissan Versa with the MR18DE engine. It is quite famous for having early failures due to piston slap, and I've got my short block replaced under warranty due to it.


I have MR20DE engine and according to this forum http://forums.nicoclub.com/nissan-versa-...nt-t386939.html the engines MR18DE and MR20DE are pretty much the same.

My engine now is at 70'000 km and has never given any problems (no slap, no oil consumption at my OCI which are ~15'000 km, no nothing).

I am also subscribed to a few European forums of Nissan and I have never heard about any problems with MR engines.

Perhaps your engine came faulty from the factory?

 

[heynow]

"early failures due to piston slap"

How exactly does the piston slap lead to engine failure?

 

[legatinho]

most engines only have piston slap when cold, for others it get progressively worse and the noise does not go away even when warm. Eventually it dies (around 60k - 70km miles). This data is for the MR18DE.

 

[legatinho]

Originally Posted By: volodymyr
legatinho,

Originally Posted By: legatinho

I have a Nissan Versa with the MR18DE engine. It is quite famous for having early failures due to piston slap, and I've got my short block replaced under warranty due to it.


I have MR20DE engine and according to this forum http://forums.nicoclub.com/nissan-versa-...nt-t386939.html the engines MR18DE and MR20DE are pretty much the same.

My engine now is at 70'000 km and has never given any problems (no slap, no oil consumption at my OCI which are ~15'000 km, no nothing).

I am also subscribed to a few European forums of Nissan and I have never heard about any problems with MR engines.

Perhaps your engine came faulty from the factory?


The MR20DE did not have the factory defect the MR18DE has. If you check the other forum, several reports of failures here:

http://www.nissanversaforums.com/engine-...-post-here.html

And here:

http://www.carcomplaints.com/Nissan/Versa/


The new short block I got supposedly fix the clearance, but after switching to synthetic the noise came back. I have no idea the Moly / MOS2 is causing this noise on my particular engine.

 

[volodymyr]

legatinho,

Originally Posted By: legatinho
The MR20DE did not have the factory defect the MR18DE has. If you check the other forum, several reports of failures here:


I see. Until today I only heard about oil consumption problem of 1.2 DIG-T engine co-developed with Renault and used in Qashqai and Pulsar.

 

[Vern_in_IL]

Any other good brand with high sodium content?

Running a 1.6 2014 versa, and have heard of the same problems with this engine.

Right now I'm running Mobil 1 5w-20(yeah I know I SHOULD be running 30 weight) and a NAPA gold.

 

[abycat]

The 20 and 18 actually can be swapped out for each other. Every plug and piece fits perfectly. Don't even have to change computer. my 2011 versa runs like a top with 60k km on it. She has had a diet of any 5w30 syn I can find cheap. only 5k km oci though. But she has seen many minus 40 cold starts without the block heater plugged in. The little car even charges my diesels batteries after I kill them trying to start it without the block heater plugged in. my car has been perfect since day 1.

 

[SwampSurvivor]

Originally Posted By: heynow
"early failures due to piston slap"

How exactly does the piston slap lead to engine failure?


Eventually the piston slap will lead to a broken piston. In the case of GM V8 engines and Honda J series v6 engines, the vehicles are junked at 300,000 miles before the piston breaks. Jeep 4.0 engines often break pistons while the vehicle is still serviceable.

 

[pbm]

Nissan went down hill when they 'married' Renault, IMO....I owned a great 1992 Sentra SER but I wouldn't buy a Nissan today....

 

[dgunay]

Originally Posted By: pbm
Nissan went down hill when they 'married' Renault, IMO....I owned a great 1992 Sentra SER but I wouldn't buy a Nissan today....


Believe it or not, Renault engines are more reliable than most of the German competitors. Even entry level Mercedes Benz cars come with Renault diesel engines in Europe.