Last night I drove my F250 from my friends house a few miles away after helping him with a heater core swap, and on the way home the transmission cooler decided to blow. I didn't realize what had happened until about 3 blocks from my house when the trans started to slip BAD. I immeadiatly pulled into the nearest parking lot in first gear, got out and saw a nice puddle of atf that had dripped from the cooler. The truck wouldn't hold on a slight hill in park, so I put it in neutral and used the e-brake. To get the extra 3 blocks to my driveway I got my friend to grab a few jugs of atf from the only gas station open in town at 1am, and I managed to slowly limp it home.
Now how much damage did I cause to the tranny? Will it last a few years down the road or will I shortly need a rebuild? I only drove it mabey an extra 200 feet after it started to slip. The truck is an 1987 F250 4x4 with a 351w and c6. Thanks in advance for your replies.

 

Wild guess, you're probably okay. Replace the cooler, refill, and see how it is. More than likely you're okay.

 

I drove from Seattle to Portland (~ 200 miles) a '77 Cutlass Supreme whose cooler was apparently leaking. I felt about halfway through that something wasn't right, but at 2 AM in the morning I didn't bother much about it, especially since I did check everything (including ATF) before I left. It was more or less OK on the freeway, but once I got to the side streets and had to stop for some red lights, I knew that my tranny was in a serious trouble. Barely, but I made it home. Next day the tranny didn't work at all. (or I didn't rev it high enough ) Since the car had an additional external oil cooler for towing, I just bypassed the leaky OEM cooler and used only the external one.

After filling up, the tranny was OK for a couple of years and about 20k miles, then became progressively bad afterwards -- hunting and jumping out of gears. Since it had about 170k miles on it at that time, it is impossible to say whether that low ATF run, or the usage with only the external cooler had caused or contributed to the demise of the tranny. They definitely didn't help, but they weren't fatal either.

I few minutes on low ATF probably didn't do much damage, if anything at all. I'd just fix the leak, refill it with clean ATF, and hope the best.

 

Thanks for the quick replies.
I'll replace the stock cooler tomerrow and hope for the best. I also plan to add on a B&M Supercooler for cheap insurance as it's only $50. I guess its also a good excuse to replace the filter while i'm at it. Thanks again.

Elderstarr

 

I doubt you hurt anything but remeber this too big of cooler in cold weather can cause problems too and it can also cause higher line pressures in cooler lines because of cold thick oil and may have contributed to your failure.

 

Tranny probably didn't get hot in this cold weather and youu wasn't completely out of fluid as you still could move somewhat. So you should be fine. Just watch the fluid level. Fill it up then drive a coouple of miles and check again. I would check it daily for a couple of days to be safe.