The tail pipe on my son's 93 Aero was broken at the famous flex joint between the cat and the muffler, so we were gonna fix it with a piece of straight pipe. so we cut the old piece out and took it to town to get a piece of pipe to replace it with and the fella at the muffler shop said it would break our motor mounts if we put pipe in. He wanted to sell us new flex pipe for $98 plus tax. Went to another shop and he made us one for $11.50 and two clamps. We mentioned above story and he said maybe it would happen, but mostly on front wheel drive vehicles. He said some have flex pipe up near engine.
We put the "hard pipe" in place of flex pipe and will see how long it will last. The second guy said it could break the pipe at the "new part". It is so far from engine I can't see it being a problem.

 

yes, the exhaust manifolds on the Aero are thin light duty cast iron...break easily and exhaust system especially at Y pipe is difficult to keep sealed....flex pipe removes most of weight and flexing of large muffler and tailpipe from twisting on exhaust manifolds....

 

I think there was a good reason that Ford installed that section of flex pipe; the exhaust system does shake a lot from the engine vibrations. If your new hard pipe is significantly stronger than the other old pipes, the old pipes will probably crack from the increased stress. I would keep an eye on things.

What they said about FWD cars is true; the engine mounts on them seem to be a lot more flexible, and they all use a flex section between the engine and the rest of the exhaust system. If they had hard pipes there, something will break very quickly.

 

Flex pipe is expensive, so you want the answer, to this question, go at it from a bean counter perspective. Would you waste the money to put in a flex pipe unless it was absolutlety needed? Now, I doubt the engine mounts would break, but the rest of the exhaust sytem not only might, but will break. The manifold(s) will crack, the y-pipe may crack where it comes together, and the catalytic converters may even facture inside. The reason it is so far from the engine, is because the engine and tranny move as one, and the hanger at the converter is bolted to the converter. This being said, you did not ask or discuss this issue on this forum, but rather took the plunge and got it done, and then seem to be asking here to see if you did the right thing.

The simplest way I can put this, is you are going to break something, and that something is gonna cost you more than the flex pipe. That price quoted may have been a little high, and maybe someone else would have replaced it for cheaper, but you get what you pay for. Also, I have cut many converters off Aerostars in wrecking yards, and that stock pipe is very hard stuff. In the unlikely even that the pipe breaks near your new hard pipe, it will likely be behind it near the muffler, where the pipe rots out. The more important stuff ahead of the flex doesn't rot because it heats up too more dureing operation. It will not break, in fact is probably harder that your new hard pipe. That original pipe is 409 stainless steel.

 

My '93 just had the flex pipe replaced because it rotted out at 220K miles. My cost from NAPA was WAY under $100 and that included the pipe, the gasket and the clamp. I could have gone even cheaper, but this is a direct bolt-in, not a fit-all. I sprayed the four bolts (two hanger, two on the flex pipe) the night before and everything came apart easily. It took less than 45 minutes for everything and now it's super quiet.
Matter-of-fact, it's so quiet now I caught my wife trying to start the van after it's already running. AARRRRGGGG! I guess I'll probably have to replace the starter soon........
Anyway, from a safe distance underneath the van look at the motor move back and forth when switching from reverse to drive and vice versa. Even with good motor mounts, it moves a lot. After seeing that, you'll probably agree that the flex pipe is the way to go.

 

The original flex pipe on his 93 has been bad for a year as you could hear the leak and we welded it once before. I guess this is the weak link in the Aero exhaust system as mentioned by other poster that the pipe in front of flex is stainless steel. Our/his exhaust system is all original with 217,000 except for the flex joint (now hard pipe) repair. I guess this will be a test to see if,when and where the weak link is now.

 

Cha its the weak link, thats the idea. You cannot weld or repair flex pipes, replacement is the only option, though there are several ways to go about it. Clamping requires a flex with sleeves on it. Welding works with both sleeved and regular flexes.