Don't use your automanual when climbing steep grades

Wuster

Member
:
Whitewater Pearl Mazda5 Touring
So we're driving back from Pittsburgh on Sunday, and I thought it would be fun to take a detour through SW PA and come back on I-68.

We stopped at Uniontown, PA to fill up with gas and feed the kids, and on the way out of town, there was a long climb up a bill hill/short mountain.

I used the automanual to keep the transmission in 3rd to maintain 55 mph (~4500 rpm) up this climb. We get about a 1/4 mile up this hill and I look out the back and we're blowing black smoke out the back (definitely an "Oh s***" moment there)

I put the transmission back into automatic mode and it upshifted to 4th and the smoke went away. I pulled over at the senic overlook to check the car and there was definitely a burning smell in the air. The transmission fluid was still pink, but it had a burnt smell to it.

We sat around for about 10-15 minutes to let the transmission cool and then resume the trip. I left the car in automatic mode for the rest of the drive and it ran fine. Downshifted to 3rd on several occassions climbing some steep grades, and didn't have any problems.

Has anyone else experienced issues using the automanual features on the automatic?

The burnt smell on the transmission fluid dip stick would indicate to me that the fluid may have been overheated, but I can't figure out where the smoke would come from.

I dropped the car off with the dealer today, hopefully, they'll tell me the transmission is fine.
 
As of this morning... 4512 miles.

We've owned the car since Thanksgiving 2005 and my wife hasn't put a lot of miles on it.
 
You put a prolonged high stress on the parts of the Automatic Tranny.

Invest in a larger oil cooler if you plan to do that again..
 
wow, that's kind of scary. not even close to when you need to at least do a partial tranny fluid replacement. try looking into an external tranny cooler and synthetic tranny fluid. the auxiliary tranny cooler will give you almost another quart (depending on size) of tranny oil, and going to synthetic will allow for higher operating temps. sounds like the tranny is being overtaxed on uphill climbs while holding gear.
 
Brian MP5T said:
You put a prolonged high stress on the parts of the Automatic Tranny.

Invest in a larger oil cooler if you plan to do that again..

Nope, no plans to do that again.

But I was surprised that the transmission over heated. We had only gone about .25 miles and I was well below redline and I wasn't towing anything.

It was also a very cool day, only about 62 degrees in the mountains.
 
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jomoyo069 said:
when you were in PA did you see Ben Rothelesberger crash his busa?

Nope, Big Ben had his crash on Monday.

But the hotel we stayed at was only a couple of miles from the accident site.
 
seems to me something else may be amiss here....i have 83K on my auto and have traveled up and down may hills...i'll take it out of overdrive mostly and occasionally drop it in 3rd, no problems no smoke???
 
Yeah, Its at the dealership being looked at right now.

The Mazda5 had a recall back in 05 for an exhaust fire issue. Apparently, the word on the street was that a couple of people burned their Mazda5 to the ground, because they drove on the highway and left it in a low gear in the automanual setting.

Mazda modified a part in the exhaust system that was suppose to fix the problem, and mine Mazda5 had the recall performed.

Car has been great up to this point. Now I'm worried.
 
Just talked to the dealer and... They couldn't find anything wrong with the transmission.

They drove it around in automanual mode and couldn't duplicate the problem and the mechanic said the transmission fluid smelled fine.

Oh well... At least I've got 45,000 miles to go before the warranty expires.
 
Brian MP5T said:
You put a prolonged high stress on the parts of the Automatic Tranny.

Invest in a larger oil cooler if you plan to do that again..

perhaps, but a tranny doesn't have an exhaust pipe attached to it!
 
Wuster said:
So we're driving back from Pittsburgh on Sunday, and I thought it would be fun to take a detour through SW PA and come back on I-68.

We stopped at Uniontown, PA to fill up with gas and feed the kids, and on the way out of town, there was a long climb up a bill hill/short mountain.

I used the automanual to keep the transmission in 3rd to maintain 55 mph (~4500 rpm) up this climb. We get about a 1/4 mile up this hill and I look out the back and we're blowing black smoke out the back (definitely an "Oh s***" moment there)

I put the transmission back into automatic mode and it upshifted to 4th and the smoke went away. I pulled over at the senic overlook to check the car and there was definitely a burning smell in the air. The transmission fluid was still pink, but it had a burnt smell to it.

We sat around for about 10-15 minutes to let the transmission cool and then resume the trip. I left the car in automatic mode for the rest of the drive and it ran fine. Downshifted to 3rd on several occassions climbing some steep grades, and didn't have any problems.

Has anyone else experienced issues using the automanual features on the automatic?

The burnt smell on the transmission fluid dip stick would indicate to me that the fluid may have been overheated, but I can't figure out where the smoke would come from.

I dropped the car off with the dealer today, hopefully, they'll tell me the transmission is fine.

if you never really driven the car hard before, then it's pretty much the first time to "break it in" and burn all the carbon out... or it could simply be running stupid rich up the hill which I have a hard time believing

so either way I think it's OK
 
Wuster said:
We had only gone about .25 miles and I was well below redline and I wasn't towing anything.

Just out of curiousity...how high did the RPMs get?
 
smaria said:
Just out of curiousity...how high did the RPMs get?

The RPM was between 4500 and 5000. I was watching the RPMs to make sure I didn't overstress the engine or the transmission.
 
I read somewhere the new mazdas are more adaptable as far as fuel managment goes. Id guess it was running pig rich to bring down combustion temps or you burnt some oil (what if the rings are not seated 100% yet??). I dunno about what mazda's do but hyundais dont blow smoke from there trans via the engines exhaust system.
 
Actually, I wasn't sure the smoke was coming out the exhaust. I was watching the tach as I started the climb. I glanced up to check the rear view mirror, and all I saw was a big gray/black smoke plume behind the car.

As soon as I slapped the shifter back into automatic mode, the car upshifted to 4th and the smoking stopped.

I traveled another quarter mile or so and pulled over at a scenic overlook. When I got out of the car, there was a brunt smell in the air (hard to discribe it). I opened the hood, and the smell was also under the hood. I checked the oil, and it looked and smelled fine. I check the transmission dip stick, and that sucker was HOT and the transmission fluid had the same burnt smell to it.

But the really strange thing was that I let the car sit for about 15 minutes and then continued on our way. (My theory being that 65 mph wind will cool the transmission faster than just sitting there letting it disipate on its own) The car ran fine for the remaining 175 miles home (I did leave it in auto for the rest of the trip). It downshifted to 3 on several occassions climbing a couple more peaks with no problems.

Took it to the dealer and they couldn't find anything wrong with the car or the transmission.(dunno)
 
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