Yes, speaking of fluid, at 60K I would have changed it twice already and be doing it for the third time. While this transmission is much better than the one behind the 5 cylinder (same transmission but with certain improvements and a much higher torque rating) they still benefit from frequent fluid changes.
If you have the transmission fluid changed, change it all, including the torque converter, which has drain plugs also. Refill is about 11 qts, cannot recall for sure because I installed a deep aluminum pan and temp gauge and so my fluid quantity was different. It can take an hour or more to refill the transmission from empty as it has a very tiny fill tube and you have to pour it in with a small cup into a funnel very slowly or it will air lock and over flow.
There are only a very few approved fluids for the Sprinter (or any Mercedes) and you need to stick to the spec fluids that are described as "Approved". That would be the genuine MB 236.14 fluid. (your owners manual may say 236.10 or .12 but .14 is the current fluid, which is slightly thinner than the earlier fluids)
Readily available fluids in the US are Shell ATF134 which is probably the most cost effective) (call a Shell distributor to find a source of it... https://www.shell.us/business-custom...r-locator.html
Genuine MB 236.14 fluid $$$$$$$$
Fuchs TITAN 4134
Pentosin ATF134 (I think O'Reilly's Auto Parts carries Pentosin products)
Here are a couple more added since I sold my MH
Valvoline ATF PRO 236.14
Most of these you will not be able to walk in and buy, as you probably will have to order them.
Here is the link to all MB APPROVED fluid spec products. The spec number on the left will be found in your owners manual, but there have been some upgrades since it was printed. Click on the spec number to see what manufacturers and specific fluids are approved for that spec number. it changes frequently as a change in the fluid required a manufacturer to resubmit the product to MB for testing which is costly. Stuff drops off the list, other stuff is added.
Spec 223.2 is the engine oil specs which is complicated to read. https://bevo.mercedes-benz.com/d/d/en/Spec_223_2.pdf
Yours is easy, Diesel Engines World Wide, Vans, without particulate filters. Follow over to the columns with the dots. 229.51 and 229.52 are the best choices, and 229.52 is not necessary for your engine and is limited to weights of 5W-30, 0W-30 or other numbers whose high weight does not exceed 30. The 229.51 has 0W-40 and 5W-40 oils also, which I prefer.
Note that the listings are for Worldwide lubricants, so there will be many you cannot obtain.
On the subject of transmission dipsticks, it is a TOOL for the mechanic, it is not part of the vehicle and is not to be left in the vehicle's trandmission filler tube. The stick is longer than it needs to be, so you slide it in till it stops and DONT FORCE IT. On the V6 you will have a couple of inches off excess dipstick showing. There are many cheap dipsticks on the market. The ends are plastic and the cheap ones tend to have the ends jam and come off in the transmission necessitating the removal of the pan, and possibly the valve body to remove the offending part.
I used this one, and had good luck with it. https://www.autohausaz.com/pn/38023
Here is the genuine MB dipstick https://www.autohausaz.com/pn/140589152100
My suggestion is you unroll it and allow the plastic end to straighten up completely. I made a tube to carry it in from CPVC pipe with a cap on one end and a fitting on the open end to stop the dipstick from going all the way to the bottom and distorting the plastic end. I carried it in the MH. You also need replacement plastic locks for the fill tube cap, as they are one use and you destroy them removing the lock. Break off the tab and use an awl or similar to push it thru and catch it and throw it away. When you pull off the cap, keep your hand wrapped around it to insure you do not lose the o-ring seal which may stick to the top of the tube instead of coming off with the cap.
Plastic locks........... https://www.autohausaz.com/pn/1409910055
or much cheaper from Amazon in packs of five
You will see many $10 to $20 dipsticks compatible to the original p/n 140589152100, but resist buying them as many people have had problems with them.