Different Take on Overheating Issue
 

Being new to the forum, I have been trying to read as many of the older posts as possible to gain as much knowledge and information as possible from the Z Community.

As far as I can tell, the most common "major" complaint I have been reading about is the oil temperature issue.

For a different point of view, I want to bring up an interesting situation that is quite similar in terms of dominating the forums.

When Porsche was building the 996 series 911s, there was a common thread regarding the failure of the rear main seal (RMS) in the 3.6 liter engine. From reading the posts on Rennlist and Rennspeed it appeared that at least 50% of owners were experiencing the RMS failure and needed new engines (which Porsche did provide under warranty to some). Porsche was aware of the engineering design defect in the engine, but thruought the life of the 996 series, they never addressed the flaw because in reality, the RMS issue affected such a small percentage of cars the fix was cost prohibitive. There were some dealers who never experienced a service call for the issue.

As I relate the above to the oil temperature issue, I think Nissan's take would be very different than the opinions posted on an "Enthusiasts" forum, which is representative of a very small percentage of owners and potential owners. So few people will ever track the car or drive it to its limits. Probably under 5% of owners.

The problem is just amplified on the forums because of the small community and heavy posters. The reality is so few of us will ever have an overheating issue that Nissan will probably view the "problem" as insignificant and not cost effective to create a design change.

No different the Porsche. That's the car business!!!

So what are you trying to say that it's just to bad. I think that most of the people having oil temp issues are concerned since most will keep the car and not get rid of before the warranty runs out like myself I worry also if the damage shows up down the road and can you guess who's gonna pay for the engine issues? well it ain't gonna be Nissan that would be my personal concern no disrespect.

Yea, I see 240 degree oil temps on a daily basis. I am worried about the long term damage that this will have on my engine. Judging on how big the oil temp issue threads are, it is not a small % of owners having the issue, but a large portion.

Just my 2 cents.

I run a marketing department for a large technology supplier... and the OP here is exactly what I'd say on a forum if I wanted people to think there was no problem when in fact there really is a problem. So, I'll just say it... you're either a shill for Nissan or for some reason you sympathize with car companies like Nissan. Nissan needs to deal with this ! Let's stop the apologies and excuse-making on their behalf.

Oh and there are plenty of former Porsche owners around here... the 996 rms issue was a dark period in porsche history and is representative of their very shift to a money-hungry machine not a sports car company. And even still, I see Porsche as going to much greater lengths to take care of its post entry into service issues... whereas nissan has yet to even take a clear position on this issue.

I assure you that I am not a schill for Nissan or a sympathizer for any car company. I am just realistic when it comes to big companies and expense justifications, especially in today's economy.

There is absolutely no way that this issue is widespread because there is not a large percentage of drivers who really "get on" there cars. If it did effect a large percentage, I would guarentee a fix would be made available from Nissan because it would effect future sales and revenue and the Z would end up as a failed project.

With the info on the 2010 now available, the changes for next year really only addessed 1 major complaint, which was the heated outside mirrors. Obviously, the oil cooler was not deemed to be necessary by Nissan.

Not widespread to all owners maybe, but what percentage of people who actually track their 370Z have the problem?

Lets design a sports car that you cant drive like a sports car, woo woo! Well, you can I guess...for about 15 minutes.

I don't know how much of this is a real problem physically with the car rather than a new safety net Nissan added to the 370Z that maybe needs to be tweaked, the 350Z did not have oil temp sensors so therefore no oil temp feedback to the ECU.

If anyone is going to track their car heavily they should add some equipment to ensure it drives safer and an oil cooler just is a smart thing to do and not that complicated.

Anyone who tracks a car expects to do the basics to make it track worthy. New pads, new brake fluid, maybe new rotors. But overheating? How many other cars honestly run into overheating in stock form, that are advertised as a TRUE sports car? That is an honest question by the way - obviously, I cant sit and research every car, but I can say I never heard mumbling and grumbling about overheating on LS1tech, that's for sure.

what is the threshold for overheating? Nissan made that definition and implemented into their ECU logic, it is not like when you overheat the coolant and it spews out the overflow, if you don't have a gauge you wont know if they oil is "overheating" and what temperature is considered overheating.

Like I said the 350Z's were probably experiencing these temps as well but just didn't know it as there was no gauge and no ECU logic to deal with it.

It will probably go down as one of those things Nissan will regret having added to the Z or at least rethink their oil temp feedback logic to the ECU.

I have it on good authority that some 350Z's DID have oil overheating problems, but the fact that there was no temp indicator and no limp mode meant that the issue was far less obvious than with the 370Z.

I'm trying to get inside Nissan's head on this one - both in the design stage and currently. Clearly they knew that there was a problem before they started to sell the car, that's why they fitted oil coolers to the cars the press reviewed.

Why did they fit the temp indicator and limp mode in the first place? Presumably because of the problems they'd had with some 350Zs and as an 'upgrade' from the 350Z? Not too sure about that one.

With the benefit of hindsight, if cost was an issue (and surely it's always an issue when you're in business), wouldn't it have been better to fit an oil cooler INSTEAD OF the temp indicator & limp mode? Too late for that now.

Will Nissan ever admit that this part of the design of their car is unsatisfactory? Well - they will never announce it to the world, but if, in the near future, a 370Z is released with a revised set-up in this area they will have tacitly admitted the design was flawed. Then they will have the problem of the several owners who feel that they are owed something by Nissan because they have engines that are prone to overheating. So, paradoxically, the complaining may make Nissan very cagey about introducing improvements in this area, for fear of admitting their mistake.

Personally, if I were Carlos Ghosn I would bite the bullet by introducing an oil cooler asap to all new cars and by retrofitting an oil cooler to all 370Z's that want one. The reason for this is that the problem is now such common knowledge that it must be hitting sales of what is potentially a really successful model for Nissan. A little money spent now on existing customers would do wonders for the sales of the 370Z over the next 6 years - and Nissan needs sales.

That's what I think.

So... I take it the RX8 is a REAL sports car then as it has not one but TWO oiler coolers!

Sorry 370Z and Nissan - You just got owned by an RX8!!!!!

J/K; that felt SOOOO good.

Nissan - You have a great product that could be a superior product. If you want to capture the rest of the market share and boost your PR (remember the GTR tranny incidient), FIX THIS!

Seeing the temps hit 240 F degrees and whether the temps are sustained the entire time you are driving the car is two different things.

Unless a person lives in a continued hot climate with temperatures above 90 to 95 F degrees all the time I don't see how the temps can be persistentently sustained at that high temp all the time. Being you live in Arizona I can see how you might have a good reason to be worried. In your case I would just do the oil intercooler and be done with it. If it ever causes a waranty issue I think you would have a good case.

But as someone alluded to, the majority of the folks aren't in your situation so for Nissan the Porshe strategy makes sense for them.

Limp mode was initiated because they changed their bearing design by dropping lead from the formulation (think eco-friendly). This meant that at temps above 300, the bearing would start breaking down faster than the older design. They noticed this and instituted the limp mode as a protection feature.

That, and unlike a rear main seal - this issue is easily corrected by installing an aftermarket oil cooler.

It must be Arizona and just a few places like that, because I live in Orlando and its hot as hell here. A couple of weeks ago it got so hot and humid we thought our home A/C had broken because it could not get the house below 78. Turns out from talking to people at work most people were having the same issue and the A/C has been fine since. yet even in that heat my car doesn't approach 240. Barely gets to 220 in regular driving with the outside temps in the high 90's.

Like the GTR. LOL

Wellllll, kinda...the appropriate statement for the GT-R is:

"Hey, lets design a sports car and advertise it as being "capable" of doing an AMAZING 0-60 time...but with a tranny that cant sustain repeated attempts at it!"

Otherwise, the GT-R is a proven track star, despite its size.

Thanks Lug - +1 rep

While true, then I assume it'd also be true with other cars that don't have an oil temp guage there for the driver to see.

For example, how about on the G37? Same engine, but AKAIK, no oil temp guage. Are they complaining as much about oil temps getting over 200F?

Why is 200F bad? or 210F, 220F, 240..260? At what point does oil become less than what it was 10F cooler? How long at 260F does it take for the oil to have measurable degradation? How many miles/months does that translate to for the average driver?

All that...lol

The article I read on the bearing problem noted 300 degrees as point break for Nissan. I have to assume the 280 degree limp mode is just a bit of cushion. As far as general oil breakdown at what temp, I really am not that well versed in oil theory to make a call.

Nor is anyone else here. The Panic is all based on emotion, not fact...

It's not a binary proposition though, there's a lot of room between "Panic" and "Everything's fine shut up". Oil breaks down under heat stress, reducing oil life. Oil viscosity drops as heat rises. Engines like to have good oil at a good viscosity to prevent excessive wear (or in very extreme cases, immediate parts failure, although I think you're more likely to run into detonation issues from overheated cylinder walls first). If you plan to keep an engine for a long time, and it's hitting high oil temps on a regular basis, you should put an oil cooler on it. It's pretty simple.

What's high enough to worry? We don't know and never will. We can put some boundaries on the issue though. Nobody thinks 200F oil temps are bad for a car, that's plenty cold. Nissan clearly thinks 280F+ is bad because the ECU kicks into a safety mode and limits revs in that range. I think if you're peaking at 260+ on any kind of regular basis, or sustaining anything over 250 for long periods, you would probably be better off with an oil cooler in terms of long-term engine wear issues, but that's just my educated guess.

Just bought my car yesterday and was driving back form PHX and my oil temp hit 255 degrees. It was 114 degrees out according to temp reading on the dash. I pulled over and sat for about 5 minutes and the temp came down immediately to about 230. Kept my eye on the oil temp from then on, but it never went up that far again. Interesting...

Except that i'm pretty sure everybody sees 210-240 degrees on average everyday when they drive.. I haven't seen someone say their oil temps are fine/normal yet with their 370.

That's what I was getting at :)

But, is 260F where oil starts to break down, or is it higher. If oil has issues at 350F - then the "weak link" would obviously be the bearings.

200F might very well be too cold - the oil might still be less than 30w oil, as far as it's viscosity is concerned.

Does anyone know what *is* normal?

If I had a good thermometer, I'd stick it on the pan of my wife's civic after she gets done driving it.

I'll say this again folks, get off your butts and read what it takes to get an oil API SM certified. It's apples and oranges compared with API SG. I don't understand why some people just can't reel in the fact that additives to oil in this day and age make them far superior to withstand the heat genereated by the newer engines of today with highly advanced technology compared with engines just 10 years ago. If it were not for better lubricants and materials engineering, we would not have these highly advanced engines available. 260 deg oil temps are yesteryear. 280 deg are today. I am not going to lose any sleep over whether or not my engine will wear prematurely unless I abuse it e.g. tracking the car. Yes, that's abuse. So protect your engine and get a cooler. Protect yourself and get a roll bar and a helmet, etc. I bet there are some folks in here who think their insurance company should pony up and make good on a claim if by some fluke you write off your car while tracking it! Or lay blame on a faulty part and expect the responsibility lies with Nissan or the race track or whatever to make good on the repairs. Anyway, these threads are still very entertaining.

Look on the sticky above! It's still going and still just as entertaining as ever. Now in three different spots! I agree with you IDZRVIT. I think it has become the opinion of the vast majority on here.

Huh? :eek: What threads are you reading?

According to Mobil's site, 400F is where their oil starts having issues.

I think a lot of us are being paranoid...or are tracking the car and pushing it to limp mode and are raising fears...

it's not just about oil break-down... if that were the only issue I agree, I wouldn't worry until I saw 320-330+. We are concerned about the materials in the engine, e.g., bearing issue referenced, that are susceptible to heat... there is a reason for the conservative limp mode setting, you can be sure

Pfft, whatever - just take it out! Its not like the old motors werent having the same problem anyway, you just didnt know it!


(extreme sarcasm, in case you couldn't tell - tired of the same people throwing out the old "just pull the gauge out and ignore it, its fine" trick...)

OP mentioned the Porsche 996. For everyone not familiar with the Porsche world the 996 has depreciated so bad that it has a resale value less that 993.

I have one word for this alleged flawed overheating issue and it's no-fix resolution: ACTUARY

Where are you going with that? actuary

That's because the 996 wasn't that great a car. Porsche abandoned the faithful with that one... Better now with the 997. The 993 will remain a classic as the last of the aircooled cars. Wish I'd kept mine..

In addition, these forums are not a good cross-sectional sample for all Z owners. 99.9% of 370Z owners do not know these forums exist mush less post anything. Of the folks that do post, they are much more likely to post something that they perceive as a problem.

And it seems they perceive literally everything as a problem. For an "enthusiast" site, the level of Automotive knowledge here is sorely lacking...

though in the same breath it should be refreshing to see so many people coming here for knowledge.

I hear that! And if BMW motorcycles are any indication, the loyalty of "airheads" will become Legend and boost the resale value of any 993 forever.