Driving style and tranny probelems

DavieGravy · #1 06-04-2002, 07:05 PM

I'm curious to find the relationship between driving habbits and how long people's trannys last. I've always been one to drive the hec out of my car and give it a good rev. I've heard that in general, transmissions shift smoother and run cooler at higher RPMs. So wouldn't having a led foot be a good thing for an SVX owner? I've read numerous posts on this issue. Some comfirming what I've stated, and others with people saying "don't race the car from a stop." So what's the bottom line on this issue?

Dave.

kuoh · #2 06-04-2002, 08:52 PM

Well I know that when I floor the gas pedal, the tranny temp shoots up accordingly. But if I get up to speed normally, I can drive for half an hour at highway speeds and not get much over 160 degrees.

KuoH

#3 06-05-2002, 11:03 AM

Transmission temperatures alone are not a fair gauge of how much work is being done by the transmission.

When I am driving hard on the 110 freeway from LA to Pasadena (ever done 110 on the 110?

) my transmission temperature is in the 160F to 165F range. As soon as I reach Pasadena and drop out of hyperspace my transmission temperature will jump almost immediately to 185F, even higher if I get caught at the stoplight at the off-ramp.

The harder I accelerate the more heat my transmission generates, but the harder I accelerate the fasater I am going, and the faster I am going the larger the amount of cooling air is rammed through my transmission cooler. At times I have found that accelerating 20mph faster will result in a decrease of my transmission fluid temperatures, even before I have reached a steady speed.

Mmmm.... 110 Pasadena freeway in my SVX....

#4 06-05-2002, 11:14 AM

is it just me, or do all subbies run really hot? My friend has a wrx and he was getting 160 - 170 while doing 100mph

kuoh · #5 06-05-2002, 11:46 AM

I don't know if 160-170 is considered hot, but the stock cooler is in the radiator and the thermostat is designed to keep the engine at 170. As Beav said, the thermostat keeps the engine at the desired temperature, but I would guess that the radiator is not too much cooler than that on an average summer day. The B&M cooler seems to be able to keep the temps lower, but only if you bypass the stock cooler completely.

KuoH

#6 06-05-2002, 02:29 PM

Quote:

Originally posted by kuoh
I don't know if 160-170 is considered hot, but the stock cooler is in the radiator and the thermostat is designed to keep the engine at 170. As Beav said, the thermostat keeps the engine at the desired temperature, but I would guess that the radiator is not too much cooler than that on an average summer day. The B&M cooler seems to be able to keep the temps lower, but only if you bypass the stock cooler completely.

KuoH

lol that reminds me, I still have to put mine in!!! it's still in the box, sitting in my garage

kuoh · #7 06-05-2002, 02:35 PM

Why do I suddenly have this mental image of some college student standing next to his trannyless SVX in the parking lot banging his books against his forehead?

KuoH

Ron Mummert · #8 06-05-2002, 02:50 PM

Quote:

Originally posted by kuoh
I don't know if 160-170 is considered hot, but the stock cooler is in the radiator and the thermostat is designed to keep the engine at 170. As Beav said, the thermostat keeps the engine at the desired temperature, but I would guess that the radiator is not too much cooler than that on an average summer day. The B&M cooler seems to be able to keep the temps lower, but only if you bypass the stock cooler completely.

KuoH

Right now I'm looking at one of those little fold-out brochures from LUBEGARD. A bar graph shows 175 as low heat (desirable),
195 as normal, 220 & above as a danger zone. Anything 260 & above predicts failure within 15K or less.

Ron.

#9 06-05-2002, 03:23 PM

Quote:

Originally posted by Ron Mummert
A bar graph shows 175 as low heat (desirable),
195 as normal, 220 & above as a danger zone. Anything 260 & above predicts failure within 15K or less.

Would that 15K be 15 klicks?

oab_au · #10 06-05-2002, 04:45 PM

Quote:

Originally posted by DavieGravy
I'm curious to find the relationship between driving habbits and how long people's trannys last. I've always been one to drive the hec out of my car and give it a good rev. I've heard that in general, transmissions shift smoother and run cooler at higher RPMs. So wouldn't having a led foot be a good thing for an SVX owner? I've read numerous posts on this issue. Some comfirming what I've stated, and others with people saying "don't race the car from a stop." So what's the bottom line on this issue?

Dave.

The heat is produced by the torque converter. The harder it has to multiply torque, under load, the more heat it will produce. Fast driving, it is locked up, no heat. In the traffic it's unlocked, multiplying torque and producing heat. Slip it back to 3rd in traffic, less load, less heat, longer life.

I don't see any problem in .the way you drive, as long as it's not in D and not in traffic.
Harvey.

DavieGravy · #11 06-05-2002, 06:52 PM

Quote:

Originally posted by oab_au

The heat is produced by the torque converter. The harder it has to multiply torque, under load, the more heat it will produce. Fast driving, it is locked up, no heat. In the traffic it's unlocked, multiplying torque and producing heat. Slip it back to 3rd in traffic, less load, less heat, longer life.

I don't see any problem in .the way you drive, as long as it's not in D and not in traffic.
Harvey.

Whenever I'm not on the highway or in stop and go traffic, I drive the car in 3. But i always accelerate very quickly and rev the engine very high, unless in stop and go traffic jams. What exactly do you meen by "as long as it's not in traffic"?

By the way, the reason why I started this thread is because I managed to char my transmission fluid in about 20k. I assume it could have been uneaven tire wear from front to rear, up untill I changed my tires. But I realized I may need to change my driving style.

Thanks, Dave

Beav · #12 06-05-2002, 07:20 PM

Look at it this way, if the trans is made to slip slightly during shifting in order to be smooth it's only a simple matter to surmise that the higher the load and speed you impose on it during that shift would be more detrimental.

Why would this even be a question? "Would it hurt more if I hit my finger with a one pound or a two pound hammer?"

Ron Mummert · #13 06-05-2002, 07:52 PM

Quote:

Originally posted by Boone

Would that 15K be 15 klicks?

Depends upon which side of the Atlantic you're driving.

Ron.

Trevor · #14 06-06-2002, 12:41 AM

Harvey you are spot on. No one with the exception of Beav has any idea of what they are talking about.

#15 06-06-2002, 06:25 AM

Quote:

Originally posted by kuoh
Why do I suddenly have this mental image of some college student standing next to his trannyless SVX in the parking lot banging his books against his forehead?

KuoH

books? oh yeah, I still have to return them