Hey yall,

I'm looking at a 2010 mustang (250k mi)with the 4.0 and 5spd manual, and was wondering what I need to look out for? I've heard something about stretched timing chains, but not much else.

Thanks!

 

The 4.0 uses a plastic thermostat housing that is prone to breaking. It is often misdiagnosed as a leaking water pump. The break usually happens on the back side and fluid goes under the intake manifold.

It's a pretty strong engine and will take a lot of abuse if maintained properly

 

I assume that would just present as liquid being around the intake manifold? Is it an easy fix/is the part expensive? Anything else to look out for? Anything with the transmission?

 

It's a very easy fix, takes about 20 minutes. It's best to replace with the aftermarket aluminum version. When it breaks it blows under the manifold and leaks down the front, which is why it gets misdiagnosed as the water pump.

 

Sweet. Thanks for the info, I'll keep an eye out.

 

I bought the mustang, and it does indeed seem to have this issue. It's got a check engine light on for a thermostat code, and it seems like the previous owner replaced the water pump... (also the timing chain, so that's awesome). Do you happen to have a link for that aluminum version?

 

Sorry, I don't have the link but you should be able to find it on ebay and Amazon

 

Something like this? https://www.ebay.com/itm/296296079057?

 

That would be the one. Getting the aluminum one avoids replacing it again when the plastic one splits again - there are some who have replaced them multiple times within a couple of thousand miles before getting the aluminum one.