3rd Generation Coolant bypass leak

Started at 41k back in April, gradually got worse. It has been sitting for a while between my work travel and summer vacation days.

I just spent an hour trying to put the new bypass back on, the two center bolts are very tough to get back in and started. Quite bit of coolant spilled out when the old bypass was removed, everything is wet and slippery.

I dropped the bolt few times, luckily I put a cover over the clutch, otherwise I would have to take the clutch out to find it.

 

Oh man, what a pain in the neck.

 

Put everything back together today.

Couldn't find the coolant bleeder, had to do it the slow way, still not sure if all the air is out of the system.

Again, it sucks.

 

Are y'all replacing with the same part? My coolant was low at 6 years 80k miles but I just topped it up and carried on. I guess I'll have to look up in there and see if I'm leaking at this bypass.

 

It takes all about 5 seconds to check it, lay down on the passenger side, look up pass the catalytic converter.

Another even easier way to tell is if you have pink coolant residue on your bell housing, chances are, it's the bypass.

 

Looks like I'm good? Hard to get a decent pic with the angle but I didn't see anything pink on or around the black plastic thing in the back or on the bell housing.

 

It's good.

 

It’s very good

 

I'm a Level II NDT examiner certified to run Dye Penetrant test and interpret indications on pressurized vessels.

I ran an quick one on the failed coolant by-pass joint over lunch break today. It shows where exactly it cracked which can not be seen easily even with magnifying glasses.

Note: of all the pictures I've seen on the internet forums, the cracks are only appearing at the Right/Passenger side flange.

 

send a report to Toyota along with an invoice and sign it from all of us

 

Sounds like a beach to do.. i was losing a quart every 4K miles and I still didn’t see anything on top of the transmission or behind the engine. Must’ve been drying fast enough as it’s leaking where it forms a crust rather than dripping. Truck only had 11k when I had the work done. It was leaking from factory I’m sure if. Install error most likely.

 

Thats cool stuff! That is the original plastic pipe right, your dying process just makes it look like aluminum?

 

It is the original part I removed from my truck.

The Dye Pen process uses a fine white powder developer which comes in aerosol can.

 

The difference is with a coolant leak you have a temp gauge on your dash and you will likely see steam once the engine has overheated, a rear end would just seize up without any prior warning. The two are nothing alike, I know you want a recall so you can try and get your money back but is it not going to happen.

 

A frame buckling driving down the road is another no warning issue, a coolant leak is not a safety item. Toyota could put out a TSB and handle it on their own but it seems they are not going to do that. NHTSA is not going to step in and issue a recall for this no matter how much you want them to.

 

@InThePlains thank you for sharing your experience. I need to do mine as well… 2016 with 90k. Does the new crossover pipe come with the o rings or do you need those or any other seals separate?

thanks!

 

Yes, gaskets on both ends, and temp sensor.

I didn't pay attention to the center pipe, not sure if there is an o-ring on it. If there is, with 90k miles, I'd replace it.

On my old 2004 Sequoia with 4.7L V8, had the coolant leaking from the o-ring into the valley of the engine.

 

Awesome, thanks!

 

Here is the O-ring part number:

 

Snagged a few pics… looks like cotton candy.