Assuming a probably put together engine, to factory specifications, that has not been raised, and that was maintained as designed with regular oil change intervals in proper oil. 50, 75, hundred, 125, 150 50, 75, 100, 125, 150,000?

I know it’s all highly individual but is there a rule of thumb on longevity? Sticking with my earlier Triumph example bearings are a regular replacement item that are usually good to do every 60,000 miles

Thanks!

Oops - should have asked if the symptoms are usually compression or oil pressure related that signal rebuild time.

My 3.0 with the stock CIS had over 200 K miles before a rebuild was required.

Type 1 and 4 stock, bottom end 150-200K is common, but the heads should be freshened up at 60-80K. A lot depends on how it was maintained and how hard its been abused.

With new heads and quality parts plus the coating maybe 100-120k. If the bottom end is done right it will last 100-150k

Thanks - good to know. The bottoms ends are pretty tough apparently.

Rebuilt mine at 325K miles, machine shop still measured 0/0 for the main bearings.
I was advised by the guy who built the heads, at 50K miles for a valve jobs. Heads have to deal with the most heat and they really take a beating, evidenced by the fact that it is really difficult to find used 2.0L heads that don't have cracks.
Other than that keep an eye on cylinder compression and leak down, when the numbers are imbalanced as 140 - 90 - 136 - 138 problem could be worn or broken ring(s) or valve seat problem. All low 80's or so tired motor.

Wow!

Thanks MG

Not a T4, I have a long time customer with a bug, I told him in the mid-90's that the engine #'s were low and he should save for a rebuild. He and his now grown up teens put over 200K since then and it's still chugging along.
He calls it the little engine that could.

I believe my stock 2.0 D-Jet ran 150K on the factory engine. She was still running good and pulling hard, but billowed a lot of smoke.

Piston ring gaps were way over the wear limit. Cam bearings showed some signs of flaking.

I'm going to try for another 150K out of the 2056.