Leak between transmission and transfer case

[Qyota]

I have a slow (at least while parked...I don't know if it's coming out faster while driving) leak where the transmission mates to the transfer case (A340F). This transmission was just replaced over the winter, so I hope I can get it fixed under warranty. My question is, is there any gasket for this? It doesn't appear as though there is one...but there also isn't any FIPG visible in that connection.

This otherwise doesn't seem to be a common place for a leak...is there another spot maybe on top of the t-case that is prone to leaking?

The fluid looks just like motor oil, but I know it can't be that. It has to be gear oil...but oddly it doesn't smell as potent as gear oil.

It's definitely NOT trans fluid.

Any ideas? It's enough to drip 4-5 drips a day probably.

Thanks.

 

[pat161]

Having just swapped a xfer case into my 02 in September I can agree that there really is not a high likelihood of a leak in between the xfer and tranny. There is a seal there but its internal where the shaft goes in, not where they bolt together. If it doesn't look red or smell like gear oil what makes you so sure it is the tranny or xfer? Could it be a rear main and its just travelling, how are all the involved fluid levels looking?

 

[Qyota]

Having just swapped a xfer case into my 02 in September I can agree that there really is not a high likelihood of a leak in between the xfer and tranny. There is a seal there but its internal where the shaft goes in, not where they bolt together. If it doesn't look red or smell like gear oil what makes you so sure it is the tranny or xfer? Could it be a rear main and its just travelling, how are all the involved fluid levels looking?

It's gear oil, it just doesn't smell exactly like the stuff I have left over in a bottle. I'll snap a pic and put it up tonight.

 

[Qyota]

Here are some photos:

 

[Qyota]

So, can anyone confirm if there is supposed to be a gasket there?

 

[ryani]

Have you checked on top of the xfer case. I noticed a small drip on the garage floor last week and found gear oil. Looked at the xfercase and it was wet all over. I traced it back to two small gaskets where the 4 hi lo shifter go into the top of the case. I only noticed it after a long road trip. The only bad part is you have to rip out your center console to inspect it.

While I was in that deep I extended the breather and made sure all the vent tubes were clear and not letting pressure build up.

I'm heading out on a road trip tonight so I'll check tomorrow and see if I solved my leak

 

[Qyota]

I have to take apart the console anyway (stereo stuff), so I'll check that. Thanks for the tip. I did notice this started leaking shortly after a long trip...

 

[Victor]

Have you checked on top of the xfer case. I noticed a small drip on the garage floor last week and found gear oil. Looked at the xfercase and it was wet all over. I traced it back to two small gaskets where the 4 hi lo shifter go into the top of the case. I only noticed it after a long road trip. The only bad part is you have to rip out your center console to inspect it.

While I was in that deep I extended the breather and made sure all the vent tubes were clear and not letting pressure build up.

I'm heading out on a road trip tonight so I'll check tomorrow and see if I solved my leak

This.

Qyota, I have replaced many of these gaskets. It happens often.

 

[Qyota]

Thanks for easing my mind, guys. I hope that's it. Victor, since you've done it many times, any pics or quick instructions for a relative noob?

Thanks!

 

[Qyota]

Bump. Haven't had time to check the shifter seal yet, but I'm kinda doubting that's it. I'll have time tonight to look at it.

What if that isn't it? What is the next logical thing? The input shaft seal?

 

[ryani]

Qyota

Success!!! I check the transfer case tonight after work and no more leak. Put about 200 interstate miles on this weekend.

Make sure you get both gaskets. They are two of them with a thin metal plate between. I used gas and oil rated gray rvt silicone and made my own gastkets.

Hope this helps you figure out your leak,

 

[Victor]

Qyota

Success!!! I check the transfer case tonight after work and no more leak. Put about 200 interstate miles on this weekend.

Make sure you get both gaskets. They are two of them with a thin metal plate between. I used gas and oil rated gray rvt silicone and made my own gastkets.

Hope this helps you figure out your leak,

I would opt for the OE orange silicone from Toyota. "Seal Packing" for manual transmissions and transfer cases. Mention that to your parts guy at Toyota and he'll know what you're talking about. Qyota, check the shifter gasket first before proceeding further.

 

[Qyota]

OK, I've taken out all of the shifter plate bolts, and disconnected the harness. What's left holding it in? Looks like the transmission shift linkage. Am I correct to assume the only place to take this apart is at the aft joint underneath? Or, is there another place I should be disconnecting this? Also, do I need to worry about the shifter moving, or the linkage moving once it's disconnected? I'd hate for it to be in the wrong gear upon reassembly!

Thanks!

 

[ryani]

Yes you have to take it loose from underneath the truck. I just made sure the bolt holes lined up upon reassembly and mine worked normal. It will leave marks because the have been together so long.

 

[Qyota]

Thanks. I should be able to finally diagnose this tonight after work. I stopped last night because I didn't want to screw anything up! I tend to do that when I get tired...

 

[Qyota]

OK, got it disassembled and took a look. It was indeed wet around the passenger side of the t-case shifter mount. It wasn't as wet as I expected it to be, but I think it may be enough for the leak I'm seeing. I cleaned it all up and put it back together so I can drive it while I source the parts.

ryani, or Victor, can you fill me in on some part numbers? I appreciate the help.

 

[Victor]

I don't know the part numbers off hand. When you go to the dealer, just say you need the transfer case shifter lever gasket, orange silicone. If you transfer case fluid is low, grab some to top up.

 

[ryani]

Qyota, I just scraped all the gaskete material off of the surfaces and then I used rvt silicone to make my own. Nearest toyota dealer is 100 miles away.

 

[Qyota]

OK, last question (for now). What happens when you remove the 4 bolts holding the t-case shifter to the t-case out? Will I need to be careful of any parts falling out? Thanks again.

 

[ryani]

Nothing will fall so to speak. The shifter has a poly ball on the end. The thin metal spacer plate that has another gasket underneath it