Fumoto valve on front diff
06-29-2018, 01:54 PM
#1
Super Member
Thread Starter
Fumoto valve on front diff
Hey all,
I'm looking at doing some more maintenance soon and one of the items on the hit list is differential fluids. The rear diff is no big deal as it has drain and fill plugs. However as we all know, the front only has a drain plug. I've seen some recommendations to overfill it via the drain port and basically quickly swap in the plug. Knowing my luck the thing would be half empty before I'd get the plug in and either not know it or have to get new fluid to try again.
I'm all about precision and as such I started daydreaming about a way to fill exactly the right amount of fluid and not have to rush the plug into place. Then it occurred to me: why not a Fumoto valve? You could install it, pump the fluid in, and shut the valve off. No muss, no fuss! According to this thread, the refill adapter for the 722.9 transmission works in the front diff, and it looks like the thread for that is 12x1.5. Based on that, the Fumoto F109SX would be a perfect fit. It's a bit spendy at $30, but I'd be very ok with that since I'm planning on changing the fluid at least a few times.
My question for you fine folks is does anyone know of a reason this wouldn't work? The only thing I can think of is it may hang too low under the car for comfort. I've also heard rumors of a vent tube that could theoretically be used as a fill point; can anyone confirm that?
I'm planning on buying a drain plug from the dealership and verifying the thread size before ordering and installing to be absolutely sure I've got the right valve.
Thanks in advance!
I'm looking at doing some more maintenance soon and one of the items on the hit list is differential fluids. The rear diff is no big deal as it has drain and fill plugs. However as we all know, the front only has a drain plug. I've seen some recommendations to overfill it via the drain port and basically quickly swap in the plug. Knowing my luck the thing would be half empty before I'd get the plug in and either not know it or have to get new fluid to try again.
I'm all about precision and as such I started daydreaming about a way to fill exactly the right amount of fluid and not have to rush the plug into place. Then it occurred to me: why not a Fumoto valve? You could install it, pump the fluid in, and shut the valve off. No muss, no fuss! According to this thread, the refill adapter for the 722.9 transmission works in the front diff, and it looks like the thread for that is 12x1.5. Based on that, the Fumoto F109SX would be a perfect fit. It's a bit spendy at $30, but I'd be very ok with that since I'm planning on changing the fluid at least a few times.
My question for you fine folks is does anyone know of a reason this wouldn't work? The only thing I can think of is it may hang too low under the car for comfort. I've also heard rumors of a vent tube that could theoretically be used as a fill point; can anyone confirm that?
I'm planning on buying a drain plug from the dealership and verifying the thread size before ordering and installing to be absolutely sure I've got the right valve.
Thanks in advance!
