Hello,

I have a 1999 E-350 Super Duty cutaway van. This rig (a small motorhome) is used only once per year. Current mileage is 38,650. I had an ATF flush done at 33,000 miles (although that was 8 years ago). Today, when checking the ATF, I noticed the dipstick had some resistance when I was pulling it out. I also noticed a couple of spots of rust on the dipstick (about 8 to 10 inches from the handle end). Resistance was greatest as the plastic bulb on the far end was passing through the slight bend near the top of the tube. (It felt like it was "dragging.") Fluid level and condition was fine, but small black particles were stuck to the fluid on the bulb. My best guess is that the dissimilar metals of the tube and dipstick were touching at the bend in the tube near the top end, and corroded each other. I think the resistance I felt when withdrawing the dipstick was caused by pulling the plastic bulb on the end through an area of the fill tube constricted by gobs of rust, which then coated the ATF with black particles. How likely is this? Maybe it is a known problem? Perhaps my situation is unique in that the rig is driven only once yearly, though I do run the engine monthy and shift through the gears. It is stored indoors. I'll be taking it to the dealer tomorrow for an ATF flush and possible dipstick and tube replacement. Anything else I should know?

Thanks,

Philip

 

I just heard from my Service Adviser at Ford. The problem was indeed a rusted ATF dipstick and filler tube. A new dipstick is on order; however, the filler tube is no longer available. Does anyone know of a source for one? The present plan is to refurbish the old one by running some steel wool through the tube and then using a parts washer. Sure would like to replace it, though. But because that is not presently an option, is there any treatment available to provide corrosion protection to the inside of the refurbished tube? Maybe pouring a very small amount of ATF in occasionally? I was also considering using a product called ACF-50. Does anyone know if using ACF-50 would harm the transmission once the product migrates down and mixes with the transmission fluid? It would be a very, very small amount of ACF-50.

Thanks,

Philip

 

I'll not overthink. It is 15 years old and once every 2 years you have check the level; of course it dried out. I'll pull the dip stick in and out four or five times every few months. By doing this, some fluid will impregnate the inside of the tube.

Painting or treating the inside may cause something to flake out and plug some ports or valves.

I am not sure how accessible this tube is from the transmission side, but if yours is soo corroded that need replacement, can you cut the flange that bolts to the transmission end and brace some copper tubing?

Just my $0.02

 

Hi GreeVan,

Brilliant--absolutely brilliant on all suggestions. Thank you.

The technician was able to reuse the original dipstick tube. Dipstick itself was replaced with new.

Are you familiar with the different ATF's? I have used Dexron for topping up in the past; invoice today said it was refilled with 12 quarts of Mercon V. Owner's Guide says to use what is written on the dipstick, which is "Mercon" (no "V"). I can't make sense of the contradiction.

Not sure which tranny I have--the 4R70W or the 4R100. Perhaps I am placing too much importance/confidence in the Owner's Guide?

Thanks again for your reply,

Philip

 

Frankly, I'd trust the owners manual before I'd trust a mechanic. I don't know about which one is right for your trans, but I do trust a dealership mechanic to just "do what he's always done and use the fluid we always use" without checking.

 

Wirelessengineer,

I did some checking as to which ATF was used in my rig and why.

MERCON V was indeed the fluid used. As to why the switch was made from the original MERCON, the transmission guy at FORD said that MERCON V is the ATF FORD now recommends for my transmission. I quoted the Owner's Guide instructions to check the dipstick handle for the recommended fluid (which states to use MERCON). He anticipated my response, and before I could finish, politely interrupted saying that if FORD could print new Owner's Guides, these new Guides would state to use MERCON V ATF in my particular transmission. I was satisfied with his response. It made sense to me.

Now to start another thread about a dragging front brake caliper...

Philip

 

Good stuff!