Where did you install the sender? Cooler lines? Pan? Screwed into the case? Or are you reading it from a programmer or OBDII interface (UltraGauge or ScanGaugeII). They will all read a slightly different temp because they are sampling the oil at a different spot in the tranny. If you are reading the converter oil temp (cooler "out" line from trans) 180-200 is pretty good. Pan oil temp would be about 150, which runs 30-50 degrees cooler than the converter generally. Unless you are pulling or carrying a load, in which case converter temp may spike lots higher

Trans temp will also depend on tire size and gearing and driving situation. Bigger tires with the same gearing = hotter (and vice versa) and city driving = hotter. My 8200 GVW (4R75W) truck runs 160-180F in city driving on normal summer days read from the valve body sensor. I have a deep pan an inline trans filter, which add a little to the cooling

Depending on where you are taking the readings, 180-200F is not overly high in and of itself, but you would wonder what it's going to be under a load. Continuous temps to 225 isn't too big a deal but over that is worrisome long term. The trans is really quite fine up to 250F continuous but the oil is oxidizing very quickly. If you change it more often, even that isn't a big problem. In the long run it's the amount of time at high temps that kills the oil. The converter temps (I can read converter out temp separately) can spike well over 250 at times when I'm working the truck hard, but the oil doesn't stay that hot long once the converter locks up.

I Have a Mag-Hytec pan, which holds 4 more quarts than normal. It knocked about 10-15F off the temp

 

My temp is from the test port. Not sure if the 10-15 degree temp drop would be worth the $300. Although the drain plug would be very nice for more frequent fluid changes.

 

What trans is in my 99 F250ld? I want to pick up a core to have rebuilt.

 

Check the sticker on the driver's door jam and check the code for the trans. Someone posted all the codes a couple days ago. Or you could just google your code question.

 

"U" code is a 4R70W, "E" code is a 4R100. If it's a 4R100 it has to be from a 5.4 or 6.8 gas engine, the diesel trans is different. If it's a 4R70W, it has to be from a 4.6 or 5.4 V8, the V6 and old 5.0 trans is different.

 

I'm pretty sure all the 7700 or 250ld F150's came with the 4r100. All the natural gas trucks are those style and they all have come with the 4r100 trans from what I have seen.

 

My 2000 7700 sadly does not have the 4r100, so make sure to check the code.

 

hmmm. Guess you learn something new everyday

 

iowaSSfan, does your 7700 have a 5.4 or 4.6 (do all 7700's have the 5.4?) I think there's a guy on the site w/ a '99 F-250 LD that has the 4.6.

Alexcngford, is your truck bi-fuel or CNG only?

 

5.4 only

 

 

my truck is a bi-fuel

 

Yup, 5.4

 

When the 7700 was the f250Ld it came with the 4.6 or 5.4, then when they changed to the f150 7700 they only put the 5.4l in them. I remember from the magazines when these trucks first came out.

 

I',m still trying to figure out what vehicle I could take the seat out of that would fit my 01 f150 reg cab, I am looking for one with a center console