Hi,

I have a 5r55e in a 2002 Mazda B4000. I put in a new cooler (larger) and a oil temperature gauge. I also put in a new set of solenoids in the valve body. Under normal operation the vehicle shifts nicely (some flare, but not bad) and the temperature stays around 140F to 155F. However on long uphill climbs the temperature increases until it gets over 210F where I shut it down to avoid any boil over or damage.

I was planning on dropping the transmission and going through it as it has about 150k miles (original as far as I know). However I was wondering if the oil I'm using could be a problem. The store here only had Wolf's Head ( https://myautovaluestore.com/wolfs-h...o-836-92866-56 ) but says "Ford Motor Company’s Mercon approved automatic transmission fluids including Mercon V"

Any thoughts about the oil or what could be causing the overheating (assuming I need to tear it down)?

Thanks,
Eric

 

Those auto trans have a dipstick right? When did u do the fluid change? Typically when you change the fluid on an automatic trans your only changing out maybe half the fluid so your basically just diluting the old fluid. what color shows up on the dipstick?

i would definitely want to figure out and solve overheating issue before you put in a new tranny because if you over heat the new one you could be putting in a new one again.

 

Where did you install the oil temp sensor?

Reads low at 155degF after warm up, expected is 180degF, general range should be 180-205degF, yes the 210degF is a bit high but not all that high if hauling a load or going up a long grade, so could be some slipping going on

The radiator trans cooler is at 170degF after engine is warmed up, that's to keep trans temp at 180degF or so, lower temp is not good either

 

I put the sensor in the port for the line pressure measurement. It seemed like the right spot. I was testing the transmission and it was running hotter than it should (hitting 230+) on a big climb and then I had a boil over. So that's when I flushed the transmission, changed the filter, the solenoids and put in the bigger cooler. The oil was darkish with signs of friction plate dust and dust in the pan.

I just took another look at the ID plate and just realized this is a 5R44E on the 4.0L! So someone must have swapped it. It's possible they didn't make any changes inside too with a 3 planet gear set and one more clutch in the clutch pack than the 55E. I don't know what impact that might have. I will say it's always shifted nicely, just hot on a climb.

 

That is odd, you would have to swap the bellhousing to do that, run a 44E on a 4.0l
55E only came with 4.0l bellhousing

44E came with 3.0l or 2.3l bellhousings

55 and 44 are torque ratings, 550ft/lb, and 440ft/lb so I doubt that would effect the trans fluid temp

 

Where I live it's not uncommon to see things like this because shipping is quite high. They might have found a used 5r44e and just used its guts.

Do you think the likely problem is just worn clutches?

 

So I have no idea if this is ur problem but this is why some people recommend not flushing a high mileage auto trans with rather dirty fluid.

as ur tranny gets more and more mileage the clutch plates wear down and the dust and particles from the clutch plates wearing leave tiny particles in your Trans fluid. On transmissions that have clutches that are about to go out with really dirty fluid sometimes is the only thing keeping the clutch from slipping. Fluid with clutch particles in it create more friction and grip than new fluid. That’s why it’s Important to change your fluid on time so it doesn’t get to this point.

Does ur truck show any signs of increased slip after the flush ? I would only ponder the possibility of worn clutch plates if ur tranny only started overheating after the flush

 

Yes, I have read that before but not sure how true it is

I think alot of people think a transmission flush will help a transmission that already has a problem, it won't, you flush transmission, or cooling system, as routine maintenance, not to FIX anything.

Once you have slipping or mis-shifts flushing won't help, the problem is not the dirty fluid, the problem caused the dirty fluid, so clean fluid won't help

So someone with a trans issue does the flush and still has same problem so flushing is a BAD thing, didn't help at all and made it worse, it didn't, problem just got worse because thats what problems do, lol

I personally don't think a trans flush is worth while, changing fluid and filter is worthwhile, BEFORE there is a problem!
Flushing cooling system is OK, if you do it yourself, not pay to have it done, and swap heater hoses at the firewall every 2 years

 

I slightly disagree Ron, when I blew the 5R55E in my Ranger, I lost all but two forward gears. It would rev way up to 5k before it would shift, but after that it wouldn't shift again. Reverse became a forward gear, as did neutral, I could drive the truck in both positions. lol. I changed the fluid and filter and all of my gears came back, Reverse turned into neutral and neutral went back to neutral. I also realized that park was a forward gear too, as the truck would back down a little when I shut it off. lol. The fluid change did help me drive the truck for a little longer, just had no reverse. The transmission was still trashed and definitely needed a rebuild. I opted to manual swap the truck and never looked back.

Pics of the carnage that caused my transmission to say goodnight, it should be obvious why it wouldn't shift. Haha.

 

I think we are all right to a certain degree. Automatic transmissions are rather complicated. And I’d say its service history should determine whether a flush is worth it or not. sometimes dirty fluid causes it to break down and become non reparable. Sometimes the dirty fluid is the only thing keeping the tranny from slipping giving it more friction. sometimes a flush will help because it’s just a high mileage transmission that’s been taken care of (fluid changed regularly). They could just be at the end of their life and it has nothing to do with dirty fluid. It just depends on the damage that’s been done that determines whether a fluid change will help or not

in the end, I say manuals ftw

just unscrew two bolts every 60,000 miles, drain and add 3 qts of Royal purple and it runs forever

 

The downside to manuals is synchronizers. The other downside is that you can't get them in real trucks anymore.

 

Automatics are all around better than manuals for car makers, traction controls, auto braking, auto stop/start(emissions), all work best with automatics, and they have higher towing numbers for trucks

For the end user, manuals are my choice, lol, but I don't make cars so don't get a vote, and apparently voting with my wallet doesn't seem to matter to any of the car makers these days
So I drive a 1994 manual Ranger

 

^+1, I swapped both my 2003 Ranger and my 1990 F350 to manual transmissions. Then I picked up my 2002 Ranger with an automatic, and all I can think about is it failing on me so I'm already considering collecting the parts to swap it as well. lol.

 

Well in my case, I bought this truck and noticed it running hot. I was hoping that maybe changing the EPC (and the other solenoids) would help with the problem. While I was at it I added the temp. sensor and increased the cooler. So I flushed it myself just because of that. It definitely runs cooler in general now. I also noticed an improvement in shifting with the solenoid change. I thought all was ok with the world until doing a long climb and I noticed the heat coming up again.

It does occasionally slip when I really try to punch the acceleration, but in general it's smooth with a little 2-3 flare.

I guess I'll need to set aside some time to drop it and inspect it because it is probably due for a rebuild. I had just never used this Wolf's Head oil before and was a little leery.