02 with 4.0L loud tapping when running

[rockingchairmoto]

Hello

New to the forum and hopefully you can help me.

I have an 02 xlt with the 4.0L motor. Son started it on a 20 degree day and it now has a very loud tap. Definitely in the driveline as it varies depending on the rpm. One mechanic said it was the timing chain. Truck starts up and runs fine. Oil pressure good. It has 170k on it but truck is inspected and lots of $$ put into it over the past few years.

I think it is a guide not the chain itself. Anyone have an idea of what it is? Is it true that I can service the front chains without removing the engine? If it is the guides is there any way to tell if it is the front or back chain?

Thanks in advance for you help

 

[extra-medium]

Timing chains. It is a package when you buy the guides so there is no sense in only changing the guides. Front/driver side can be done without removing the engine, but passenger/rear has to have the engine removed. Might as well do the whole job if you are gonna do it, only downside is it's about a 2500-4000 repair depending on what shop you go to.

 

[Tech By Trade]

Much easier to search the wreckers and find a low mileage drop in. Any 4.0l sohc from a mustang, range rover, explorer, ranger or sport trac will fit. Post 02, or newer the better. About a 20 hr job to swap it.