Horrible rust due to poor design (1 Viewer)

[GremlinMobile]

Perhaps this is widely known, but I just noticed this yesterday and wanted to share my frustrations. I noticed a puddle under my GX470 yesterday. I went to inspect it and it was just AC condensate. But when I was on the ground looking up to where it's coming from, it was leaking off the frame. It wasn't obvious at first, but it's the AC condensate drain that drips onto the frame, and if the car is parked on any kind of incline, the condensation runs along the frame and drips down from this area. Well that area is REALLY rusty. Like crunchy rusty. When I poked it with my finger, it was like BBQ flavored Lays potato chips started falling on my face. It was crazy how much rust is in that specific area. Talk about a design flaw. There is no provision for letting the AC water get to the ground without touching half-ass painted steel. That particular part of the frame appears to be VERY compromised and makes me wonder how close it is to a catastrophic failure. The truck has under 200K which I thought I could easily take to 300+, but seeing what I saw last night, I might have to give it up in the next year due to this crappy design.

What a shame.

 

[Jstawgn]

I extend mine to below frame using simple barb and 3/8" hose.

AC condensation are basically distilled water and the PH are 7. But for some reason they are a lot more corrosive than rain water.

 

[GremlinMobile]

I extend mine to below frame using simple barb and 3/8" hose.

AC condensation are basically distilled water and the PH are 7. But for some reason they are a lot more corrosive than rain water.

Of course that a great solution. I did that on my old land cruiser. For some reason when I got this GX, I didn't check to see if this design flaw exists, but oh it sure does. Warning to all to do the hose barb mod, because as I see it, that's what may make the difference between these things turning into a pile of rust vs going to 400k miles over the years..

 

[HomersCanyonero]

Of course that a great solution. I did that on my old land cruiser. For some reason when I got this GX, I didn't check to see if this design flaw exists, but oh it sure does. Warning to all to do the hose barb mod, because as I see it, that's what may make the difference between these things turning into a pile of rust vs going to 400k miles over the years..

Good to know. My 2003 has been in SoCal all its life. I run the ac all the time.

I need to check to see if there’s any rust in that area.

Any photos of the area in question or the extension?

 

[stupidchicken03]

Since the front seats and middle row each have their own AC, are there two drains? Or do both systems drain from the same area?

 

[GremlinMobile]

Good question. I'm not sure about a second drain but I would guess the front AC drain is at least the primary one since for most users that's the one that gets used daily. I'll take some photos.

When I bought this car 3 years ago, I had the seller pressure wash the undercarriage and spray it with rubberized undercoating. I feel like it made it rust faster... This particular spot is destroyed. It's like pouring water into a steel bowl with rubber on the outside of it to prevent it from ever draining..

 

[Rednexus]

The rear AC drip line goes straight down in the rear PS wheelwell. I don't think it has much of a risk of any rusting issues with it.

The front is a terrible design indeed. I relocated it on mine as well - with a hose barb and some 3/8" hose. It now daylights next to one of the frame crossmembers.

My rig has some rust inside the frame in that area. I have coated it with a ton of Fluid Film (inside the frame) and Woolwax Black (outside) and it has stopped progressing. The steel in the frame is only 1/8" thick, if a few potato chips flake off the frame might be compromised.

I would suggest using a similar treatment on your rig. The lanolin-based undercoatings work much better than a "hard" undercoating.