Big Coolant leak over transmission (1 Viewer)

[Toyotaoh]

1996 Land Cruiser. 245,000 mi.

I noticed a wet area under the cruiser this morning- reseviour was low as well. I let the truck warm to operating temperature and crawled underneath. The leak is over the transmisson, behind the engine. I took a rag an wiped either side of the transmission down. It wetted again very quickly but I cannot see, topside or underneath, where it is leaking from. It is significant enough that it starts from the top and makes it all the way to the rear of the tranmission and is making quite a mess of my driveway.

I just had the throttlebody bypass hose done about two months ago. I have also done the PHH and rear heat bypass two years ago.

Any thoughts on this?

 

[bulhas]

is it possible the rear heater hoses were never drained and now they are just leaking out what was left

only thing I can remember that would be leaking there, granted, you should check that your bypass isnt leaking down the trans tunnel

 

[Toyotaoh]

Thanks. I thought the same thing, but this is an active leak once the truck is at operating temperature. When you mentioned the bypass, are you referring to the PHH?

Edited to say that I checked both heater core connections and the top of the PHH- its all dry. What ever the leak is its significant. Hoses down below and under the intake are dry as well. I can believe that something that is spewing that much coolant isnt more revealing!

 

[Toyotaoh]

Just some more clues. Antifreeze is dripping around the entire tranmission pan until it reaches the rear and leaks on to the cross member behing the transmission. Added to this, because of the driveway the truck is angled slightly forward so anything engine and forward, I would think anyway, would travel towards the front of the truck.

Is there a coolant hose or hardline traveling to and from the transmission? Could the transmission or someplace rear of the engine itself be leaking?

 

[Tools R Us]

Heater valve and/or line leak?

 

[Tools R Us]

Best to use a pressure tester, so you can look for the leak with the motor cold.

 

[cme4lyt]

Rear heater lines !

 

[bloc]

Is there a coolant hose or hardline traveling to and from the transmission?

No. The only coolant related lines that go to the transmission area are the rear heat lines. Obviously the heater core connections are above the bellhousing.

Possible head gasket leak at the rear of the head and running down the bellhousing to the top of the transmission?

 

[shocktower]

I am thinking, either rear heater hoses, or head gasket,

 

[Toyotaoh]

What about leak in the heater core?

I thought that head gaskets leak in, not out?

 

[shocktower]

What about leak in the heater core?

I thought that head gaskets leak in, not out?

Heater core is inside the cab, it could be one of the penetrations, through the fire wall

 

[Rifleman]

Rear heater hard lines may be rusted out, or the rubber lines that connect to them above your transmission.

 

[Toyotaoh]

Thanks all. I deleted the rear heat about two years ago using the rear heat bypass method due to the hard lines rusting out.

 

[Death Star]

I'm going through the same thing. It looks like I'm leaking externally, right under #6 exhaust port. Check there.
Is there a freeze plug on the back of the block?

 

[Toyotaoh]

I think this is all adding up. I have noticed a hot smell- like something dripping on the exhaust, on and off for about a month now. I have a dirty engine and I just assmued with all the recent rain perhaps road spray was mixing with the oily residue on the engine and splashing on the exhaust. Plus, I have had a CEL for an O2 sensor...when I did a data stream from both up and down stream sensors they both appeared to be sending a low voltage signal. I am wondering if an internal leak lead to the fouling out and failure of the sensors?

At any rate, it appears there is a head gasket in the future for this vehicle. I will likely do the short term route and use K Seal in the cooling system to get me through till I decide what to do with the truck. I only drive it about 8 to 10 K miles a year, so it does not get a ton of usage, and I have heard an additiive can buy a decent amount of time. I don't see it as a permanent fix as I would like the peace of mind knowing that I am not going to have another HG blowout at an inopportune time (not that there's ever a good time).

 

[Death Star]

I think this is all adding up. I have noticed a hot smell- like something dripping on the exhaust, on and off for about a month now. I have a dirty engine and I just assmued with all the recent rain perhaps road spray was mixing with the oily residue on the engine and splashing on the exhaust. Plus, I have had a CEL for an O2 sensor...when I did a data stream from both up and down stream sensors they both appeared to be sending a low voltage signal. I am wondering if an internal leak lead to the fouling out and failure of the sensors?

At any rate, it appears there is a head gasket in the future for this vehicle. I will likely do the short term route and use K Seal in the cooling system to get me through till I decide what to do with the truck. I only drive it about 8 to 10 K miles a year, so it does not get a ton of usage, and I have heard an additiive can buy a decent amount of time. I don't see it as a permanent fix as I would like the peace of mind knowing that I am not going to have another HG blowout at an inopportune time (not that there's ever a good time).

I used Blue Devil head gasket sealer and it got me through the winter. It's a process to do correctly but it held up ok. The Cruiser is at the shop getting the HG done right now.

 

[White80]

Sounds exactly like what I had a while back. Mine turned out to be the lines right behind the head going into the firewall (below the heater control valve). These hoses will make you wish it was a PHH. Absolute pain to get to and install new ones. Took the better part of the day, countless cramps, lots of profanity and one fall out of the engine bay. In the end I have all new hoses back there and have been leak free since.

 

[Toyotaoh]

I purchased k seal earlier this year do to another leak that turned out to be the throttle body bypass hose. This time it appears I was not so lucky. I went ahead and poured the k seal in the radiator and the leak has completely stopped. I don't this this works on a line, so I can only assume at this point HG. That said, it kind of puts things on the clock. Not sure I want to invest in an HG and I don't have the band width to do in on my own right now.

 

[McNasty]

I know this thread is old, but did it end up being the head gasket? I've been chasing a similar leak.