Check Your 3.5l Coolant Pipe!

That's wild. I could have had it same day, but flicked it to 2day delivery in my garage. Just easier with all the porch robbers.

Lemme know how you like it.

 

The 3.5 did not have plastic pipe on the Lexus either. This was an upgrade by Mike Sweers, along with the delete of the transmission cooler to improve the QRD

 

Makes me wonder if the hook in the end is sometimes being used to assist in engine installation at the assembly line. If so, that would explain some failures. I would be tempted to try some plastic-weld if I could locate the exact leak point

 

What are the other reasons?

 

I could be wrong, but it looks like it could be the support for this connector:

 

Yes I saw that and it appears to be its main purpose. However, during installation I'm wondering if its sometimes used to ease installation.

 

Just shooting from the hip, but I would not think so. I believe the driveline is assembled on the frame first, then the cab is tossed on top? With all that room, I think they would have a bunch of more useable points of supporting the engine / transmission combo.


In his thread, I think @Jowett had a theory about the mold design that contributes to the leak issue. I'll see if I can find it.

 

Here's his thread, but no comments on the design:
https://www.tacomaworld.com/threads...for-plastic-rear-coolant-bypass-joint.701890/

 

No, what you say makes sense I'm just thinking there may be some maneuvering of the engines from the time its assembled in one factory, to the time its assembled.
Its really just me shooting off at the hip trying to find a logical reason for the failures because that should not be happening as it is, or creating worries about ownership.

 

I couldn't find the post that I was looking for. Given that the part is fiber reinforced nylon and has some steps in some area of the mold, bad infill or porosity in the mold combined with heat and pressure cycling could be the explanation. Fiber reinforced nylon is stronger but more brittle than plain nylon.

 

The only reason I think of the hook being used to maneuver the engine around from one place to another is because I've seen it done in other applications (makes/models) to maneuver them and since the hook is there, it maybe tempting to some to use it.

Plus it make me sleep better thinking that mine may not have been used like that lol!

 

Hahahaha! It is silly if the mold is flawed and they used a million of them.

Of course, there have been plenty of flaws in metal castings also.

 

They need to do a tsb for this and fix our shit

 

I feel like way less people have the leaking bypass than the leaking 3rd brake. And the 3rd brake housing just came out. I think a tsb is a pipe dream at this point lol

 

I tried looking with my new endoscope today, but couldn't find that coolant pipe (having a hot engine didn't help). I'll try again tomorrow with a cool engine and see if I have better luck.

I like that endoscope though, it works great!

 

Hot would not be fun.

Slide it between the firewall insulation and the plastic harness support channel just forward of it. For me, I had to get at it from both sides of the Taco.


Excellent! I'm glad that you like it.

 

From what I heard the 2016s and early 17s were only affected by this.This was what amd said on the car care nut.He is a master mechanic for Toyota.However if this is your problem,Toyota drops the motor from the truck do to location of coolant pipe which is why it is a small fortune.

 

Makes sense that the heat cycling could kick it off. When I go snow wheeling or do any extensive hill climbs I used to smell coolant from time to time. Its been since replaced and (although I haven't visually checked yet) I haven't smelled coolant again.

 

That's great to hear. Hopefully it stays that way (for all of us).

 

I purchased same endoscope just haven't had a nice day to check coolant pipe are weather has been super shitty