I know on the old la motors about 100k miles is a very good time to change one seems like I jumped timing on several between 101 and 110 k anck in the 80's. I have a 99 5.9 with 95k when should I think about tearing the motor down and doing timing chain?

 

yeah, ive heard 100k and theyve got some good slack in em

 

i changed mine while doing water pump at about 125K. it was pretty worn out and had a lot of slack.

 

Are there any mods to do while I have everything torn down?

 

some people choose to advance or retard the crank sprocket 4*. i didn't feel like i understood that, and i knew i didn't want to tear it back down if it didn't work out right.

you'll want to replace front seal and water pump and water pump bypass hose. check for leaks on rear seal, if its leaking you might want to do it and oil pan gasket.

you sig says you've already fixed the plenum, so no need to tear into the top.

 

Mine still has the original.

 

Mine was a slack as vaughan's was at 60k. It's overdo.

I think my Cloyes HD chain is loose with another 35K on it. The fuel sync wobbles about +/-4* on the snap on scanner. I researched a better chain with some guys who really beat on their engines, and they recommended a JP performance chain. It's sitting in the garage ready to be installed when I order my new cam.

 

i got 193K and mines the original chain. motor runs mint