improving mileage
Elder User
Joined: Dec 2006
Posts: 559
Likes: 4
From: On a farm.
What revs will these engines sit on happily as a maximum. Mine is 7.3 factory turbo that is basiclly stock as far as i know. At 100km/h in o/d i am doing about 2000rpm. Not sure of tyre size or diff ratio. If I put it out of o/d to tow I can only do 80km/h. Can these engines handle prolonged running at 25-2800rpm for instance or is it ok to tow in o/d on flat country. I have found the auto starts to get warm on long trips towing in o/d.
Senior User
Joined: Nov 2008
Posts: 319
Likes: 0
From: Western Australia
110km/h is the highway limit around here, 100km/h if towing. David85 I dont really understand why I would go smaller tyres and higher revs? I can do around 100km/h while towing out of o/d with about 2800rpm and just wanted to be sure the engine will be ok with this.
Lead Driver
Joined: Nov 2003
Posts: 6,900
Likes: 3
From: Campbell River, B.C.
110km/h is the highway limit around here, 100km/h if towing. David85 I dont really understand why I would go smaller tyres and higher revs? I can do around 100km/h while towing out of o/d with about 2800rpm and just wanted to be sure the engine will be ok with this.
But again, it depends on what your transmission temperature really is. By the book, your setup is already ideal and I suspect an aftermarket cooler would be the real solution if your tranny is really overheating.
Senior User
Joined: Nov 2008
Posts: 319
Likes: 0
From: Western Australia
I have coolers coming out my ears. In front of my radiator I have air con cooler, power steer cooler and 2 heavy duty trans coolers running in parallel. The auto was rebuilt after the po cooked it, the trans guy put the coolers in but the problem I think is the standard 5/16 lines. They are too small to be efficient. I am going to build 1/2 inch stainless tube lines and incorporate an inline trans filter as soon as I get time. The trans doesn't get hot when not towing and it has only reached 200-210 twice but when it does the o/d light flashes and when I get it checked the code says exessive converter slip. The lock up seems to work fine as I have tested that according to my manual. The two times it has got hot has been in summer towing a good sized load in o/d. As a result if the trans gets to 180-190 now I either back off or come out of o/d.
Senior User
Joined: Nov 2008
Posts: 319
Likes: 0
From: Western Australia
Ok just to add some details, I belive my diff is 4:10 like dave said. My tyres are 265/75-r16 and the temp sender is in the sump bung of the auto. Dave how do I convert tyre size to on road speeds and what are the auto ratio's assuming the lock up allows for no converter loss.
Lead Driver
Joined: Nov 2003
Posts: 6,900
Likes: 3
From: Campbell River, B.C.
210 is the upper limit of the safe range. That shouldn't cause problems unless something else is wrong. Are you sure your converter clutch isn't letting go? That is a known problem with the E4OD transmissions. The apply clutch piston develops cracks that relieve pressure and prevent enough force for proper holding power. The result is slip, and heat.
Bigger cooler lines are a good idea idea, but I think your problem may not be solved by that.
Bigger cooler lines are a good idea idea, but I think your problem may not be solved by that.
Post Fiend
Joined: Oct 2008
Posts: 8,513
Likes: 2
From: concord ca
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Lead Driver
Joined: Nov 2003
Posts: 6,900
Likes: 3
From: Campbell River, B.C.
I do find it curious that the builder would install a billet converter with only one friction element in it. Generally most aftermarket converters have 2 frictions even if they aren't billet.
There should have been an inline filter installed on the return side of the cooler at the time of the rebuild. This is actually required under ford warranties but not everyone else does. The idea is to prevent any shrapnel from the old transmission from getting knocked loose and killing the new one. Do you know if the factory cooler is still connected or if such a filter was installed? Sometimes they can become partially restricted. I am actually running my transmission on two series connected auxiliary coolers with the radiator cooler bypassed completely.
210 is still ok, but not ideal and you don't want to be spending all day there. Since the temperature is being measured at the pan, the internal temps are at least 10F hotter. If you have that much cooling in there, it shouldn't be running that hot. I am glad to see that the center support bearing has been upgraded though. Thats worth it's weight in gold.
Did the code scan reveal any sensor malfunction?
There should have been an inline filter installed on the return side of the cooler at the time of the rebuild. This is actually required under ford warranties but not everyone else does. The idea is to prevent any shrapnel from the old transmission from getting knocked loose and killing the new one. Do you know if the factory cooler is still connected or if such a filter was installed? Sometimes they can become partially restricted. I am actually running my transmission on two series connected auxiliary coolers with the radiator cooler bypassed completely.
210 is still ok, but not ideal and you don't want to be spending all day there. Since the temperature is being measured at the pan, the internal temps are at least 10F hotter. If you have that much cooling in there, it shouldn't be running that hot. I am glad to see that the center support bearing has been upgraded though. Thats worth it's weight in gold.
Did the code scan reveal any sensor malfunction?
Senior User
Joined: Nov 2008
Posts: 319
Likes: 0
From: Western Australia
Cooler in rad is totally bypassed. No filter that I have been able to find. No other codes when it got hot. I have had other trouble with trans before. When I got the truck the cruise control did not work. I messed around trying to test it and eventually swapped the unit out. It worked for about two days and then it stopped working and the trans started shifting strange, Snatching gears and changing up and down irregularly. I took it to the shop and it said the vss out of range code was up. They tested the vss and it was ok. Next I took it to an auto sparky and he looked at it for about three days. Finally it turned out if you disconected the cruise control unit from the connector and left it unplugged it was ok, just no cruise control. I have left it like that and had no further problems with the auto and can live without cruise control.
Lead Driver
Joined: Nov 2003
Posts: 6,900
Likes: 3
From: Campbell River, B.C.
The VSS also drives your speedometer, cruise control and your rear axle ABS. If that was a problem, I can understand the transmission and cruise going out of wack at the same time, but I never heard of the cruise causing the PCM to get confused except on my truck (but I run an aftermarket controller).
There is a "range sensor" on the - um in your case its on the passenger side of the transmission on the shift lever. That is called the "manual lever position sensor, or MPLS sensor usually. That can also cause strange problems and it can be tested with an olm-meter and also has to be aligned properly to work. There is no adjustment for the VSS. Either it works or it doesn't.
Does your speedometer read perfectly steady? that can be a sign if a fault in the VSS somewhere (sensor, connector or related wiring).
There is a "range sensor" on the - um in your case its on the passenger side of the transmission on the shift lever. That is called the "manual lever position sensor, or MPLS sensor usually. That can also cause strange problems and it can be tested with an olm-meter and also has to be aligned properly to work. There is no adjustment for the VSS. Either it works or it doesn't.
Does your speedometer read perfectly steady? that can be a sign if a fault in the VSS somewhere (sensor, connector or related wiring).
Senior User
Joined: Nov 2008
Posts: 319
Likes: 0
From: Western Australia
Vss good, no problem with speedo,mpls seems ok as well. As I said the auto only plays up when you plug in the cruise control. Not really phased though as if and when I get to it I will put in aftermarket cruise. Will do upsized trans cooler lines and then see how that goes this summer. Need to find out how to convert tyre sizes to road speed and will look at changing tyre sizes from there.
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buckmeister2
1987 - 1996 F150 & Larger F-Series Trucks
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Jun 24, 2002 06:18 PM
