C4 leak possible overfill?

[blamejane]

So I noticed a small amount of ATF under my bronco a couple of months ago, and went ahead and picked up some fluid from Napa and added it. I think I might have over filled it, but I can't be sure. At the time I don't think I realized I was supposed to be checking the levels with the engine HOT (as per the dip stick). I think I might have just let it idle for a few minutes and started adding fluid, while checking the stick. Fast-forward to a week ago when I drove my bronco to town and back. When I arrived home to park, I notice a LOT of ATF on the ground under my bronco. I can't say how much because I have a 3' by 4' piece of cardboard that sits underneath for leaks. However, this piece of cardboard was completely saturated corner to corner; soaked in, not in a puddle on top. After doing some research I decided to drive it to town and back so that the engine was good and HOT, after which I checked the tranny fluid level. It didn't even register on the stick. I'm assuming now I have a bad leak, either the pan gasket or somewhere else. I watched a few YouTube videos on C4 leaks, as well as read a few threads here on the forum.

I sprayed degreaser and let it sit overnight. Today I power washed the undercarriage so I can detect the leak and parked it back in the garage. Now what should I do? How long do I wait? Should I add some ATF? Will the leak appear over time?

Back when I originally added ATF, I do remember at the time thinking I had added quite a bit of ATF; thinking wow, must have been really low. So maybe I added too much, and that's why there was a mess on the floor. But if that's the case, why would the fluid read empty on the stick next time I checked it (while HOT)? I would think that it would still register some amount of ATF if things were fine here. I certainly don't want to destroy my tranny, so how can I be sure.

Today, before pulling it out to power wash, I checked the ATF levels and found the fluid read in the "don't add" section. I know it's meaningless to check cold, but I thought I would at least mention it.

Anyway, just wanted to give all of the details I can think of.

Thanks Valerie

 

[Yeller]

Valerie
Is the leaking fluid still nice and red? I’m sure it was, but the engine was running when you check it? If you did overfill it, when you drove it very possibly it came out the vent, no harm done other than a mess. But if it was low to begin with, that points to a leak.

Procedure for checking the transmission is with the engine running, pull the dip stick, wipe it off, reinsert and pull again, the fluid level should be between the near the bottom of the “do not add” if cold, if hot, near the top.

Hope this helps.

Steve

 

[blamejane]

Thanks for the support Steve, yes the fluid was nice and red and the engine was running while I checked it. It was definitely low to begin with as you said.

I'm gonna see if any leaks show up overnight.

 

[Yeller]

Your welcome. Always trying to be helpful and contribute to our great community full of great folks

If it has just had minor drips, I would crawl underneath and pull the fill plug on the transfer case. If a little oil comes out that is normal, if it gushes out that is where your transmission fluid went. If it gushes the transfer case will need pulled and the seal replaced. Not saying that’s what is wrong but something easy to check that gets overlooked.

 

[blamejane]

Your welcome. Always trying to be helpful and contribute to our great community full of great folks

If it has just had minor drips, I would crawl underneath and pull the fill plug on the transfer case. If a little oil comes out that is normal, if it gushes out that is where your transmission fluid went. If it gushes the transfer case will need pulled and the seal replaced. Not saying that’s what is wrong but something easy to check that gets overlooked.

Awesome, thanks so much Steve.

I'll update this thread with my progress

 

[hyghlndr]

They will leak real bad when over filled.

 

[blamejane]

24 hours after power wash, here is where I see the drips. I'm gonna say the gasket needs replacing.

Let me know if you guys think I can still drive the bronco while keeping an eye on the ATF level? I'm going to order the gasket, but it's tradition on the last day of high school since freshman year, my grandson has always driven the bronco. I'm hoping he can do the same this year, his junior year, but of course I don't want to damage anything. I don't think the gasket will be here in time to have it replaced.

Thanks y'all!

 

[Slowleak]

You may just have some loose pan bolts. I have to re-torque mine occasionally. I would put a wrench on them and check. Specs call for 12-16 ft/lbs. Tighten them up, wipe the fluid off, and see what happens.
It’s fine to drive unless you are losing quarts of fluid…which you are not.

 

[blamejane]

You may just have some loose pan bolts. I have to re-torque mine occasionally. I would put a wrench on them and check. Specs call for 12-16 ft/lbs. Tighten them up, wipe the fluid off, and see what happens.
It’s fine to drive unless you are losing quarts of fluid…which you are not.

Excellent idea to check these bolts, appreciate the support.

 

[ba123]

Yeah, just cause you see the fluid there does not mean it's coming from there. Could be coming from forward of that and moving back, esp if you drove it at all!

 

[blamejane]

Yeah, just cause you see the fluid there does not mean it's coming from there. Could be coming from forward of that and moving back, esp if you drove it at all!

Thanks, I will keep that in mind. Maybe take if for a little spin.

So when the stick says, "HOT" before checking fluid, how long should I let it idle? Or does it require a bit of driving to get "hot"?

 

[ba123]

fill, shift through the gears, put it in neutral, check again.

If you don't have a temp gauge, you'd be surprised how long it takes to get warm and I think it needs to be over 100° to be an accurate measurement and that can take some time and really, what makes it warm up is the torque converter working and that happens in gear. It will warm up eventually if in gear and brakes applied but I think a spin is better.

Also matters if your dipstick is correct...assuming you have a stock dipstick? I have an aftermarket one I had to figure out what was right which was even more of a pain.

*** And HOT means the TRANS, not just the Engine!

 

[blamejane]

fill, shift through the gears, put it in neutral, check again.

If you don't have a temp gauge, you'd be surprised how long it takes to get warm and I think it needs to be over 100° to be an accurate measurement and that can take some time and really, what makes it warm up is the torque converter working and that happens in gear. It will warm up eventually if in gear and brakes applied but I think a spin is better.

Also matters if your dipstick is correct...assuming you have a stock dipstick? I have an aftermarket one I had to figure out what was right which was even more of a pain.

*** And HOT means the TRANS, not just the Engine!

Okay great, thanks for the info. I do have a temp gauge, if you mean an infrared temp gun. I have the stock/original dip stick too.

 

[Viperwolf1]

Pan gasket is pushed out from over-tightening. Need a new gasket and probably need to flatten the pan rails before installing it. Use no sealant.

 

[blamejane]

Pan gasket is pushed out from over-tightening. Need a new gasket and probably need to flatten the pan rails before installing it. Use no sealant.

Thanks Viper, I just finished watching a few install videos for the gasket, and definitely see how the gasket is supposed to be clean edged along the pan, not squished out. I thought this video here showed a good demo. He did use a small amount of ultra black sealant, though it was a composite gasket. I'm not sure if mine will be cork, but it's on order from Wild Horses, so we'll see what I recv. The gasket on my pan is really squished out around the pan...I also see some rips/tears in the gasket as well. Not sure if this was done to compensate for a wobbly pan or not.

 

[blamejane]

Just a quick update: The new gasket and filter arrived. I took the bronco for a drive, making sure to move through all of the gears to bring the engine/tranny up to HOT temps. With the engine running I added ATF until the dipstick read full; this time making sure the bronco was parked on a level surface. I then checked for leaks over the next few days, but nothing more than a few drips appeared. I even drove to town a few times and still nothing much as far as leaks. Each time I return from town I check the fluid level, and so far so good. I'm eventually going to change that squeezed out cork gasket for the new one, but in the mean time I'm just keeping an eye on the tranny levels and driving the bronco.

Thanks for everyone's help here. Truly the best forum EVER!