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Mechanic busted exhaust manifold

A few months ago we replaced the catalytic converter on our 1999 Toyota Sienna. Within about a month, the exhaust started making a rattling noise. Took it back to the mechanic, who said the converter was bad, and would be replaced under warranty. I took the car in yesterday (took them a while to get the part in), but when they went to remove the bad converter, the bolts on the exhaust manifold were corroded, and they stripped them getting the converter off. Now they say they need to replace the manifold. There’s no labor charge, but they’re going to charge me $250 for a new part.

Should I pay this? This was supposed to be a free in-warranty repair job. It’s not their fault that the bolts were corroded. But…it still rankles to be charged for warranty work.

It seems like a fair deal to me. I’d pay it.

It seems strange to me that the same bolts they successfully removed a few months ago are now too corroded to be removed without stripping them. I wonder if they should have used new bolts a few months ago and charged you a few bucks then instead of $250 now. Or, I wonder if they used new bolts that were made of inferior grade metal.

Still, stuff like this happens with old cars and given the uncertainties, it’s probably a fair deal.

One possibility is that they originally used a universal converter, did not have any room left in the front pipe for more cutting and welding, ordered a direct fit part this time, which included the front pipe, then were unsuccessful in removing the bolts. I don’t know if this is the case or not, but it is a good possibility. Either way, these things do happen from time to time, the price is reasonable for the part, and they are not charging you labor to replace a part that will most likely be a royal pain in the butt to change out. This seems like a fair deal to me.

This happens all the time with exhaust manifold connecting hardware, and the manifold doesn’t require replacement. The exhaust manifold has threaded studs screwed into it, and nuts are used to connect to the manifold. If the nuts are rounded, there’s special tools to remove them. If the studs are stripped, these can be replaced by unscrewing them from the manifold and installing new ones. If the studs are snapped off, these can be removed by centering a nut over the broken stud, and then thru the center of the nut weld it to the broken stud. Once it cools, unscrew the broken stud.


Joys of an older car.

I would be grateful for the $250 charge myself.

the reason these studs and nuts and associated parts rust out so badly, and often so soon, is that there is a lot of heat dissipated through these parts. That speeds up the oxidation process. If the warranty covers the entire exhaust system, they should not charge you, but if it only covers the converter and muffler, then they can and should and will. You need to read the fine print on your warranty to find out which it is.

See if they will use a used manifold from a salvage yard. I replaced a cracked manifold on my pick-up with a salvaged one for $30. Since it is 12-years old, there should be plenty available.

You should pay because the exhaust manifolds of today are made from tubing instead of heavy cast iron. They won’t hold up to normal repair work.

It’s not so much that you should pay; it’s more like the mechanic shouldn’t have to pay for modern manufacturing. The emphasis is on fuel economy and a lighter car will use less fuel.

You should definitely pay.

The mechanic is working on a 12 year old car. Rusted exhaust manifold bolts can be a nightmare to deal with. He didn’t ask for the headache of removing old rusted bolts from your manifold.

Maybe his mistake was to not let you know the risk of dealing with the rusted manifold bolts ahead of time and the potential extra costs involved.

If, at the start, he said to you:

I will try my hardest to get the manifold bolts out successfully, but if they break, the price of the job will increase by $XXX.
would that have made you feel better about it?