Tranny Temp
Lead Driver
Joined: Dec 2002
Posts: 5,493
Likes: 16
From: Kuna ID
Originally Posted by Casey
That chart is completely useless for any modern transmission or ATF. If you are running a 1960's fluid, then pay attention to that chart.
You are also correct about the giving of misinformation, we don't really need any of that. I guess I will get rid of that link now, or at least not expect it to apply to everything(I forget things are improved with time). At least I learned something from all this. Now I am gonna go cook some of this egg I got on my face. 
Logistics Pro
Joined: Nov 2002
Posts: 4,788
Likes: 20
From: Mansfield, TX USA
Originally Posted by Sycostang67
You are also correct about the giving of misinformation, we don't really need any of that. I guess I will get rid of that link now, or at least not expect it to apply to everything(I forget things are improved with time).
Like I said. I am going witht he Ford gauge (or the idiot light in my CTD). When it goes off, I'll worry. Until then, I will just change the tranny fluid per the severe service schedule.
Lead Driver
Joined: Dec 2002
Posts: 5,493
Likes: 16
From: Kuna ID
I try to stay in the 180-200 range, but is it the fluids that allow for the temp, or are the trannies made today being built with different materials that make them withstand more heat? I run MERCON V in my 85 F-250(C6), and while I hope I never get to 248* it would be nice to know which would be the weak link, chemical or mechanical.
Logistics Pro
Joined: Nov 2002
Posts: 4,788
Likes: 20
From: Mansfield, TX USA
Originally Posted by Sycostang67
I try to stay in the 180-200 range, but is it the fluids that allow for the temp, or are the trannies made today being built with different materials that make them withstand more heat?
FTE Legend
Joined: Jul 2005
Posts: 65,938
Likes: 1,432
From: Millersville, MD
Originally Posted by Casey
I agree with jschira. It's both better materials in the trans and better fluids.
Lead Driver
Joined: Dec 2002
Posts: 5,493
Likes: 16
From: Kuna ID
Originally Posted by jschira
My PSD has 2. Oil to air and oil to water.
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Fleet Mechanic
Joined: Mar 2004
Posts: 1,398
Likes: 17
From: Hesperia, CA
My 77 F250 C6 has two coolers on it. I think I am going to pull the lines off of the radiator and put the largest cooler I can buy in place of it. I have a 22K aux cooler mounted under the vehicle and I still can't keep the tranny fluid under 220. The gauge is mounted in the tranny pan and under hard pulls up hills the tranny will get up to 250+ the tranny has 220k miles on it and is still working ok, but it still makes me nervous running that hot. I have been using merc V in it ever since the stuff came out. Also I change out the fluid every 25K and run an external filter.
Senior User
Joined: Jan 2006
Posts: 117
Likes: 0
From: Annapolis, MD
My E4OD took a dive a couple weeks ago, so I had a shop install a Jasper rebuilt E4OD, along with a temperature gauge (and a drain plug to make fluid changes easier). I believe they installed the gauge sensor in the pan. The Jasper transmission includes a new cooler, btw.
When I talked to them today, they said they've taken it on several test drives and the temperature hasn't climbed above 150 degrees. (This is a 9,000 lb motor home.) Since I'll be towing a car with it, it sounds like I should start to worry around 220 degrees or so. However, if it's doing 150 solo, hopefully 220 will be a pretty rare occurrence even when towing.
The transmission's first test will be to pull a car over the same mountains that caused the other one to die. It'll be interesting to see what the temperatures do in those mountains, since they're about the worst I will encounter in my travels.
When I talked to them today, they said they've taken it on several test drives and the temperature hasn't climbed above 150 degrees. (This is a 9,000 lb motor home.) Since I'll be towing a car with it, it sounds like I should start to worry around 220 degrees or so. However, if it's doing 150 solo, hopefully 220 will be a pretty rare occurrence even when towing.
The transmission's first test will be to pull a car over the same mountains that caused the other one to die. It'll be interesting to see what the temperatures do in those mountains, since they're about the worst I will encounter in my travels.
Last edited by rmarquet; Jul 19, 2006 at 08:56 PM.
Senior User
Joined: Jan 2006
Posts: 117
Likes: 0
From: Annapolis, MD
Brand new (well, rebuilt) Jasper E4OD in my motorhome, with a gauge in the pan: it does about 150 degrees solo, I had it up around 165-175 when towing in the mountains with O/D off... then 180-190 sitting in traffic on the DC beltway.
Interesting, but not surprising that sitting in traffic (after working hard all afternoon) would be what got it warmest. It was fine even climbing the hills on I-70 near Fredericksburg, MD.
Interesting, but not surprising that sitting in traffic (after working hard all afternoon) would be what got it warmest. It was fine even climbing the hills on I-70 near Fredericksburg, MD.
