175 to 200 max but 175 To 180 is the best! They say at those temps you should get 100000 miles on a trans with relative ease!! jb
2001 F 350 CC PSD 373 rear,auto
RBW X16 slider,Bedsaver,Prodigy,Fold A Cover,Pressure Pro!
2011 Crossroads Cruiser cf32mk Patriot edit. 5th wheel Fibreglass and all the goodies necessary,Dish,comfy loungers,and a nickel to spend,
Mr & Mrs and the PUP.
This chart and several variants have been regurgitated ad nauseum all over the internet and in general should be disregarded. No one has ever been able to produce any data behind what the testing parameters were or how the conclusions were reached.
This chart may have been the case 30 years ago but design and materials have improved substantially over time. Fluids are much more durable as well as transmissions. My 2011 F350 normal operating temp is 195F. So according to this chart my transmission life will be somewhere between 50,000 and 100,000 miles? I don't think so.
Unknown to some, "too cold" is as bad as "too hot". When ATF gets too cold, it gets thicker, it harder on the pump and harder on its seals as well. If below -15F temps (like in my woods), I would wrap the aux ATF cooler with a thick water resistance blanket (re: thick plastic bag). Vision someone wearing winter "wind break" coat during extreme cold winter months. If wondering, I mounted my vehicle's aux cooler 1" away from its AC rad. This gapping allows me to "winter wrap" my vehicle's ATF cooler from mid Nov to mid March. re: - Click Here -
Hope this tip helps as well...
* This post was
edited 06/27/11 10:07am by batman99 *
Before I'd jump all over getting a bigger cooler, what were some of the circumstances of the deal?
How are you reading the trans temp? Where is the trans temp sensor?
What was your driving conditions like? ie, going up a hill, stop and go traffic, running on a level hwy?
How long have you been monitoring your trans temp?
Do you have any past readings doing about the same thing where the temps were lower?
How hot was it outside at the time?
IMO, adding an additional cooler to the mix isn't necessarily going to net you lower temps either... Depending on your specific trans, it may not like another cooler added? If anything, you would want to replace the OEM one with a larger cooler of the same design.
I thought I needed a larger trans cooler, or one with a fan on it after I first got my trans temp gauge installed and towed with it initially....
Turned out that when I said that it would run at 180* for the most part on the flats and only rise in the hills, or in stop and go, but once I got going again, it would come back down to 180*, the sales guy said that it would be a waste of money for my to change what I've already got... I thanked him and I'm still running the same OEM cooler and towing the same TT some 9 years later with no trans issues...
*Anything I post is for entertainment purposes only and what usually works for me.. Your Mileage May Vary..
IMHO, While newer synthetic fluids can take substantially higher temps internal transmission parts and seals may not be as forgiving…
For general discussion the 200* temp is a established long time reference point, even though it may not apply to each fluid or each transmission… all transmissions and fluids should work well at that temp, and some have diminished capacity at temp above that…
Larger coolers may not substantially reduce the normal operating temps of the fluid but they can definitely prevent temperature rise and the duration of the higher temps… this will extend the life of the fluid and possibly the transmission… it would be rare and unusual for the temps to be so low in operation to be damaging but I guess it is possible in extreme situations… then the bigger problem would be warm up time before driving…
So it may not help and waste money but chances are slim to none that it would hurt anything…
the money might be better spent on a engine oil cooler and a coolant filter…
Love my mass produced, entry level, built by Lazy American Workers, Hornet
My 2010 5.4 6sp runs at 183 all day except when towing. Then it goes up to about 190-195, but will stay around 185-187 on flats. FWIW my 08 F150 5.4 3.73 4sp ran around 160 all day. When towing it would be all over the place. Up as high as 205. Both F150s have identicle tow package and drive train. Only exception being the 6sp in the 10. All rigs are a little different and it's really hard to compare. I would call your chevy dealer and ask them what is okay.
IIRC the best temp for a modern tranny is around 160 to 180 for lubrication/efficiency purposes along with removing moisture from the fluid. Some of this might apply to older dino fluids and not as applicable to the newer synthetic fluids. Those temps should be pan temps again IIRC.
I've monitoring by tranny temp for 10 years now, 75K total and 40+K towing at 80 to 85% of my 20K GCWR and have never seen a temp over 200 and generally max out at around 190 and that is over many, many mtn roads and in all weather conditions. I hit that 200 on I-80 going over the Sierras out of Stockton, CA into Nv. in May of 2004 when I got boxed in behind a semi and ended up in 2nd with TC unlocked screeming along at almost 3K rpms and 25 to 30mph.
I have only the stock cooling on my Van and a handful of times when my tranny gets past 190 my coolant temp is getting just over 210 and then my engine fan comes on and starts dropping the coolant temp and basically stabilizes the tranny temp in the 190 to 195/200 range.