[sam_p_barr]

Hey guys.

So recently I leaned a lesson on trail about departure angle and it resulted in my stock exhaust pipe getting bent up pretty good. I was planning on replacing the stock exhaust system anyway, so I got to searching.

I found a set I liked from Flowmaster and it gets tucked up into the truck underneath, however I have 2 concerns.

What are the chances this sucks up water during wading, given how short the pipe is, as well as what are the chances of exhaust fumes getting into the cab considering it dumps under the truck?

I like that it gets tucked up under before the rear axle, so my departure angle in the back has more clearance, but I want to get an idea of everyone's thoughts before sending it.

Appreciate it everyone. 👌

 

[debFJVT]

Better safe than sorry…I’m pretty sure @PureFJCruiser carries high tuck tailpipes and could answer your questions. I have a high tuck (arcs just over the rear frame member) and never once have even come close to hitting it, and I do some pretty hardcore rockcrawling.

 

[norm356]

Q1: "What are the chances this sucks up water during wading, given how short the pipe is?"

If you don't turn off your engine while under water the positive pressure from the running engine will not allow water to enter to exhaust (note that deep water calls for a raised air intake but typically the exhaust is fine).


Q2: "what are the chances of exhaust fumes getting into the cab considering it dumps under the truck?"

The chances are pretty good that fumes can come into the cab, especially if there are any gaps in the body sealing, anywhere. Note the cabin vent is on the LH side, just behind the rear tire and fumes could come up it, if its flaps are not sealing. So long as you are moving forward and you don't open the back window, it might be ok, but if running the engine while sitting still the risk of CO entering the cab will be worse than stock.

 

[Glenarch]

I would be concerned about CO entering cabin thru center counsel as there are open bolt holes in there, you also are going to raise your rear axel temp while on the interstate which will lead to more fluid changes and premature failure on bearings. For a dedicated crawler I like the design if it is being trailered. As deb stated a high tuck would be safer.

 

[Datajockeys]

This is what I’m getting.

URD Spec-U Exhaust, FJ Cruiser, 2007-2014 - Underdog Racing Development

URD is proud to announce our new Spec-U TUNED exhaust system for the 2007-2014 FJ Cruiser. This is the ultimate performance exhaust system for your truck and it is ready for off road racing. The Spec-U system differs greatly from our other exhaust systems and Y pipes. We took a totally...

urdusa.com

 

[NyNomad]

out the back is no different than underneath. As long as the engine is running exhaust pressure should be more than water pressure which will keep water from back flowing into the exhaust. I've been in deep water crossing a creek. I survived crossing twice.

 

[Iconic_]

I have a custom exhaust that dumps right before the axle. More noise enters the cab so it can be a little loud. From what I understand the only issue with fumes is when they are allowed to pool under the vehicle due to built up snow around the sides of the vehicle and its sitting idling. Never had an issue or noticed fumes myself. Yes it heats up the axle tubes more.

All that said, I would recommend a high tuck tailpipe that exits beside the rear frame rail.

 

[NyNomad]

now with a remote starter I can say definitively for my specific FJ that no exhaust gasses leak into the cab(refer to previous post for picture)