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The fill plug on the transmission is hard get to and impossible to see in to. My concern is getting the crush washer out at that location. I'm thinking to only open the control plug and drain plug for a fluid change and fill through the control plug until the fluid reaches the hole like is done on many vehicles.

Am I missing something? Are others doing this?

Am I missing something?

Yes! Since the "control plug" is on the right angle fitting (I assume this was done to get the level to be where it needs to be due to the rotation of the tranny) if the fluid level is lower than it should be but is still high enough to keep oil in the fitting, no air can escape as oil is added - so suddenly the oil seems full to the level of the plug but the level within the tranny is much too low. You need the fill plug to be open to either put oil into or to allow air to escape if you add oil to the level plug. The easy way is to remove the tranny cover from the bed to access the fill and level plugs, however I have removed the fill plug by feel from underneath without removing the tranny cover; it can be done. I then used a clear plastic hose stuck on the end of a quart bottle spout to get oil into the fill plug hole. .

If the crush washer comes out with the fill plug, then you know it is out. If the plug comes out without the washer then I would assume that the washer is sitting in the fill opening where it should be. Since the fill plug is not "wet" (not below the oil level) I just put the plug back in and don't worry about replacing the crush washer, it is not likely to leak much since it only sees splashes of oil.

Jimm391730 wrote:

Am I missing something?

Yes! Since the "control plug" is on the right angle fitting (I assume this was done to get the level to be where it needs to be due to the rotation of the tranny) if the fluid level is lower than it should be but is still high enough to keep oil in the fitting, no air can escape as oil is added - so suddenly the oil seems full to the level of the plug but the level within the tranny is much too low. You need the fill plug to be open to either put oil into or to allow air to escape if you add oil to the level plug. The easy way is to remove the tranny cover from the bed to access the fill and level plugs, however I have removed the fill plug by feel from underneath without removing the tranny cover; it can be done. I then used a clear plastic hose stuck on the end of a quart bottle spout to get oil into the fill plug hole. .

If the crush washer comes out with the fill plug, then you know it is out. If the plug comes out without the washer then I would assume that the washer is sitting in the fill opening where it should be. Since the fill plug is not "wet" (not below the oil level) I just put the plug back in and don't worry about replacing the crush washer, it is not likely to leak much since it only sees splashes of oil.

Thank you very much!

we have actually seen where people check their fluids without removing the top plug and allowing the air/oil to balance. Oil is trapped in the 90 degree fitting and when plug is loosened they see oil and think it is full when in reality there was only a small amount of oil in the tranny. I am sure it was an expensive learning experience for that owner. Funny thing is he said that the tranny leaked but was never low on oil. I guess he missed the clue. Always pull the top plug to let the air equal out when checking level and adding/changing fluid.

almost forgot, a lot of us have cut the allen wrench so it will clear the body and allow removal of the plug. I think it takes about 3/8ths of an inch off to make it work.

4x4Pinz wrote:almost forgot, a lot of us have cut the allen wrench so it will clear the body and allow removal of the plug. I think it takes about 3/8ths of an inch off to make it work.

Thanks for the tip!