Ok it’ colder than a Witch’s you know what this winter, so here’s the question, will an automatic transmission warm up faster in Neutral than it will in Park?
Do the pumps do something in Neutral that they don’t do in Park? Did we used to check the fluid level with the transmission in Neutral because the pumps are porting fluid?
John D said
Jan 29, 2014
Any device will warm up faster "under load", but then there's the risk of breaking something asking it to perform when it's not at temp. Catch 22.
The 4L60's in Green Mary & Blackie have a thermal switch on the cooler line that won't allow the converter to lock up until the fluid's up to temp.
SShink said
Jan 29, 2014
John D wrote:
The 4L60's in Green Mary & Blackie have a thermal switch on the cooler line that won't allow the converter to lock up until the fluid's up to temp.
I'm guessing it's a 4L80e in my 2003 GMC, but it doesn't lock up into OD until things are warmed up. Sometimes that's 15 min. into my drive home from Bloomington with the temps as low as they've been, and the truck is cold soaked all day from sitting out in the open parking lot...
SteveS said
Jan 29, 2014
SShink wrote:
John D wrote:
The 4L60's in Green Mary & Blackie have a thermal switch on the cooler line that won't allow the converter to lock up until the fluid's up to temp.
I'm guessing it's a 4L80e in my 2003 GMC, but it doesn't lock up into OD until things are warmed up. Sometimes that's 15 min. into my drive home from Bloomington with the temps as low as they've been, and the truck is cold soaked all day from sitting out in the open parking lot...
Usually the computer raises shift points when it's cold too, trying to get it to warm up quicker.
Bungy L-76 said
Jan 29, 2014
The trans will warm up the same between N and P. The only difference is a mechanical arm is engaged against a "gear like ring"" when in park. I always check the fluid when in park.
Lost in the 60s said
Jan 29, 2014
SShink wrote:
I'm guessing it's a 4L80e in my 2003 GMC, but it doesn't lock up into OD until things are warmed up. Sometimes that's 15 min. into my drive home from Bloomington with the temps as low as they've been, and the truck is cold soaked all day from sitting out in the open parking lot...
Our trucks have the 4L60e transmissions. The 80's are for diesel and 2500-3500 series.
I just changed the filter and fluid on mine at 122k. Fluid was NOT pretty !! The pan was clean so I don't believe I left the fluid in past a critical point. Just a reminder for those who never change fluid until there is an issue...
dashboard said
Jan 31, 2014
I found this on the web; the reference is to Jeep transmissions. I have experimented with warming it up in neutral with temps below zero and it makes a difference. I know someone going to say, start the thing and after a minute moderately for a quicker warm up but I don't like sitting in a cold car while it warms up.
"There is a difference. In fact, your transmission in your vehicle does not circulate ATF through the transmission OR cooler or even the converter when in "P". It goes in then directly out of the pump and dumps back into the pan. So in your case it would be beneficial for you to warm up your transmission when in "N". This is also why you check your fluid level with the gear selector in "N". Now if you were driving a Chevy Tahoe for instance, the transmission would warm up in "P". This is also where you check your fluid level."
Lost in the 60s said
Jan 31, 2014
dashboard wrote:
I found this on the web; the reference is to Jeep transmissions.
Now if you were driving a Chevy Tahoe for instance, the transmission would warm up in "P". This is also where you check your fluid level."
The warm up procedure for your Jeep doesn't apply to our GM vehicles.
I've never owned a Jeep and was surprised that they check the fluid in "N". I haven't seen an auto trans dip stick that specified checking in "N" since the 50's models.
In your new shop, you can have an exhaust hose with a flapper and autostart on the Jeep. Leave it parked in N with the park brake set and start it from the house...
SShink said
Jan 31, 2014
Lost in the 60s wrote:
In your new shop, you can have an exhaust hose with a flapper and autostart on the Jeep. Leave it parked in N with the park brake set and start it from the house...
Probably no need for that in Kevin's new shop, as I'm sure it will be sunny and 75 all the time since it will be heated, and no warm up needed.
Ok it’ colder than a Witch’s you know what this winter, so here’s the question, will an automatic transmission warm up faster in Neutral than it will in Park?
Do the pumps do something in Neutral that they don’t do in Park? Did we used to check the fluid level with the transmission in Neutral because the pumps are porting fluid?
The 4L60's in Green Mary & Blackie have a thermal switch on the cooler line that won't allow the converter to lock up until the fluid's up to temp.
I'm guessing it's a 4L80e in my 2003 GMC, but it doesn't lock up into OD until things are warmed up. Sometimes that's 15 min. into my drive home from Bloomington with the temps as low as they've been, and the truck is cold soaked all day from sitting out in the open parking lot...
Usually the computer raises shift points when it's cold too, trying to get it to warm up quicker.
The trans will warm up the same between N and P. The only difference is a mechanical arm is engaged against a "gear like ring"" when in park. I always check the fluid when in park.
Our trucks have the 4L60e transmissions. The 80's are for diesel and 2500-3500 series.
I just changed the filter and fluid on mine at 122k. Fluid was NOT pretty !! The pan was clean so I don't believe I left the fluid in past a critical point. Just a reminder for those who never change fluid until there is an issue...
I found this on the web; the reference is to Jeep transmissions. I have experimented with warming it up in neutral with temps below zero and it makes a difference. I know someone going to say, start the thing and after a minute moderately for a quicker warm up but I don't like sitting in a cold car while it warms up.
"There is a difference. In fact, your transmission in your vehicle does not circulate ATF through the transmission OR cooler or even the converter when in "P". It goes in then directly out of the pump and dumps back into the pan. So in your case it would be beneficial for you to warm up your transmission when in "N". This is also why you check your fluid level with the gear selector in "N". Now if you were driving a Chevy Tahoe for instance, the transmission would warm up in "P". This is also where you check your fluid level."
The warm up procedure for your Jeep doesn't apply to our GM vehicles.
I've never owned a Jeep and was surprised that they check the fluid in "N". I haven't seen an auto trans dip stick that specified checking in "N" since the 50's models.
In your new shop, you can have an exhaust hose with a flapper and autostart on the Jeep. Leave it parked in N with the park brake set and start it from the house...
Probably no need for that in Kevin's new shop, as I'm sure it will be sunny and 75 all the time since it will be heated, and no warm up needed.