Exhaust question

2017 trd sport. Im putting the stock exhaust back in the truck and I noticed the bolts on the flange don’t have the springs. Should I just bolt up the exhaust with the same bolts or should I buy the bolts with the spring? Also will the autozone spring bolts work if I need those bolts? Or should I wait for oem to ship

 

Typically spring bolts are used only when a donut style gasket is between the pipes, this allows for some flex in the system. If it's a standard gasket shaped like the flange then spring bolts are not needed. Without looking at oem setup I couldn't say off the top of my head which style it uses but that's typically what I see

 

My 22 has the same bolts. As stated the springs are used for connections that allow for a small amount of flex. Commonly found on unibody chassis where everything has some flex.

 

It's got nothing to do with unibody construction. Flex connections are usually at the exhaust headers, to allow for the flex/movement in the motor induced by the motor mounts.

 

There are no springs installed at that location.

 

Looks pretty clean. Lot of rust on the flange has been documented

 

No springs, only bolts and flange nuts on these systems. The flange nuts are factory welded on.

Toyota parts counter will give you the run around and the wrong bolt size. I went through this when swapping to the trd catback a couple of years ago.

Go to Home Depot and find the Everbilt hardware section. You'll want M10-1.25x35mm flange bolts and M10x1.25 flange nuts. Or you cap tap and die the rusty oem flange nut.

You might need the exhaust flange gasket. (sorry no part number on hand)

 

Also, PB blaster penetrant spray those bolts really good and let them soak a while before attempting to remove them.

 

Any day you learn something new is a good day.

I had never seen springs on BOF vehicles just unibody so I figured that was the deal. Would make sense as they do flex more where the engine mounts are.