Hello All, I bought a 2007 F-350 last spring for odd jobs around my property. The guy I bought it from had just replaced the transmission pan because the old one rusted out. Unfortunately the new pan has leaked ever since I got the truck. I’d periodically check the dipstick though always when it was cold (I know that was dumb) and it showed fluid in the cold range. I don’t drive it much but it had been shifting fine until one very noticeable slip / buck at highway speed the other day. That got me thinking about more seriously checking the fluid level. I followed the recommendations of driving until it was warm and shifting through the gears before checking the dipstick. To my surprise, there was nothing showing on the dipstick! I bought some fluid on my lunch break today and added a full quart plus about 12 oz from a second bottle. It’s hard to get a good reading when you first put it in so I checked it again after work. The cold level was certainly higher, maybe just into the H range. After driving home, I checked again to get a warm reading but it is still not registering on the dipstick. Should I continue to add more fluid? I don’t want to overfill it. The transmission shifted fine today both before and after adding the fluid. I appreciate insight. This is my first SD. I’ve always driven Fords, but either cars or SUVs.

 

If nothing else Id run it sitting idle and check the fluid after 10 or 15 mins. If your checking it cold, not running, the torque converter and other parts of the trans may be draining back into the pan. Obviously taking it for a spin on the highway is the best option but your call. Yes, after adding fluid its a PITA to get a reading as the tube is coated with fluid and it makes it hard to see what going on. Thats the case on my 99 SD anyhow.

 

My understanding is that the cold range is to get you close enough so you don't damage the trans when replacing the fluid. The real test is getting it to operating temperature and adjust accordingly while the transmission is running, the truck is in P and on level ground.

 

If it doesn't register on the dip stick I'd say it is still low. At least a quart low. Check hot, engine running.

 

My latest decision on this is to leave it more on the low side once up to temp. If you get a reading when warm and it shifts fine, leave well enough alone. The new LV and ULV fluids seem to really expand with heat. FTM even mentions this in some of his vids.

I think this is also why manufacturers have moved away from dipsticks, requiring you to check fluid level with a scan tool and a standpipe at the pan itself. I don't like this, but that's another topic.

 

Thanks for your replies. I added more fluid today, the rest of the second bottle plus two more, so a total of 4 quarts has been added. It looks like it’s finally showing at the very bottom of the dipstick while running and in park. I’m going to leave that for now and monitor it as I don’t have any more fluid. I’m really surprised it was that low and still shifting fine.