For the first time since SLICK was new I got a "AT CHECK" warning on my dash and she went into limp mode. Dropped by Infiniti only to find my extended warranty ran out months ago. When I restarted her everything was normal which I was happy about but concerned about the warning. Waited a couple days and she drove fine without a recurrence. Went to Nissan had them check any codes to find out what the cause was....nothing! Tech said the fluid had a burnt smell so I had them drain/refill but that's only 3+ quarts out of 10 so at my next oil change I'll have it done again and probably a few after that. Strange you can drop into limp mode without a code of any kind....
Gary

 

The AT Check Light should of put a code into the TCU, they have to use a consult II to read it.

If they tried that and no go, then nothing you can really do until it happens again.

 

What were the circumstances under which the AT check light came on and the car went into limp mode? Were you stuck in traffic on a hot day? You'll go into limp mode if the AT fluid gets above 260F (or thereabouts).

 

Did you check the fluid level to make sure it's full?

 

It was a warm day here in the Santa Clarita valley, 105 degrees and I was waiting at a stop sign when the warning showed up on the dash. Went to leave with traffic and SLICK would hardly move. Once I restarted her everything was fine except for my concerns. Like I posted fluid smelled burnt but it was full and only had about 12k miles on it. But that's not true cause at 30K I did a drain & fill which is about 1/3 of what the trans contains. Most of the fluid has over 40K miles on it, maybe there's something to be said for a total flush in warm climates like mine?
Gary

 

Sounds like it just overheated. You're on the right path with the drain & fills.

 

Trans will not go into limp until 390F.

If you are not pushing it 180-200F is usually what the trans will be at since its cooler is attached with the radiator.

The OEM trans cooling is lacking IMO which is why I personally installed a cooler for it.

https://g35driver.com/forums/engine-...r-install.html

 

Your 390F number has come up before, but its way too high. I watched my AT go into limp mode a few minutes after it hit 260F in October 2010 while stuck in traffic heading onto the Bay Bridge (I have a temp sensor in my AT fluid pan). The deets are in a thread over on my350z (your 390F number is mentioned there as well):
http://my350z.com/forum/engine-and-d...mperature.html

I agree with you though on the normal operating temperature, and kudos on a very well put together DIY

 

Thanks, spent a bit of time organizing it all heh, hope it helps everyone out.

Interesting, I talked to a guy who has a boosted 5AT and he says he saw 300F from his cooler lines on Tail of the Dragon and it did not go into limp mode. There are two temp sensors, one in the VB and the other.. no idea where the other one is but we can assume its somewhere internal.

 

Seb at SpecialtyZ mentioned he does a drain/fill of his AT every second oil change, sounds like good advice living in a warm/hot climate....Gary

 

As long as it's still red (not brown/black) and doesn't smell burnt, it doesn't need to be changed. I'm in FL and it's plenty hot here. Changing it every 6-10k miles wouldn't hurt, but the stuff isn't cheap.

 

When mine heated up I noticed tiptronic wouldn't let me shift into 5th... But I never had the check AT on.

But what was said earlier about the cooling lacking on our ATs is especially true. If you've got a transgo (can't remember if you do)- then cooling would be the next step for sure.

 

Members like BigC that are knowledgable and have the TransGo kits also run trans coolers and likely gauges to keep an eye on the temp. I average 5K miles a year on SLICK so doing a drain & fill isn't going to dent my wallet but I want to get most of the fluid out that has the burnt odor....Gary

 

Checked with the trans shop in my area this morning, trans cooler installed is $350=. Seems reasonable to have it done right. Don't want to have my trans fluid getting burnt and SLICK going into limp mode again. Seem reasonable?
Gary

 

Considering you can buy a tranny cooler for $40, I would say no. But it all depends on if the labor is worth $300 to you