My new optimizer made it 70,000 miles untouched. Then spun a cam bearing from the flashing coming free. It ruined the bearing and the cam obviously. I stopped it in time before the spinning bearing ruined the block.
Now here’s the thing- where is your oil pressure gauge attached?
Center of the valley right? Half way down the camshaft right? The bearing that spun is after the sensor. On my engine the oil pressure gauge was at the rear of the engine- opposite of where side mounted turbo oil supply is at. So I had a couple bearings after my sensor that still restricted flow as they should before the spun bearing. So my oil pressure drop was only a 10 psi drop from where it was the day before, but still way high that is considered good oil pressure.
Only because I constantly note the gauges And noticed the difference when I heard a funny sound and a momentary blip in power did I take it seriously. Knowing that it is usually the very last (front) cam bearing that gets damaged, and since I was planning on adding my centermount turbo soon anyways which required me removing the engine the way I was doing it- I removed the cam and saw the problem. It would have kelt running and had oil pressure for maybe another 1,000 miles then ruined the entire engine- block crank, etc.
I knew when I put it in the smarter choice would be disassemble, inspect and reassemble even if I made no alterations. NO WARRANTY. But I justified it by saying “GEP builds these for war fairing equipment- millions and millions of new engines are made every year- this should be fine.”
No. DOGE should be inspecting AM General- specifically GEP because the failure rate of the 6.5 is absolutely horrendous. They are slapping these engines together by standards thought ok in the 1970’s except the absolute worst unbalanced lower rotating assembly any one at any machine shop has ever heard of. Why? THERE IS NO FACTORY SPECIFICATION AS TO BALANCE!! They just slap together and figure it’s ok. Meanwhile modern engines have a specification because they learned it makes a difference in not just longevity but efficiency. Better mpg and emissions.
If a person doesn’t want to upgrade rings, coated bearings, or doesn’t even care to get the balance closer by diy methods- (if broke and don’t know how, ask) then fine.
But buying an $8,500 engine that seem to have a chance of catastrophic failure in under 100,000 miles… spend another few hundred dollars and ensure it will live a lot longer life.
Disassemble. Throw away the gaskets and head bolts & main bolts. Sit down with a $20 die grinder and $20 bit (if you dont already have them) to remove all the flashing. Maybe 3 hours if you never did it before and have the worst cast one ever. Use $5 in plastigauge and check clearances if you dont have the better measuring tools. 4 hours.
A $10 scale from amazon will let you use same die grinder to get rods and pistons amazingly close to equal. Yes the crank being done is a big improvement but rods & pistons are half the battle and a guy can diy them close in a single day. The new gaskets and bolts are not expensive. Head bolts-$50, head gaskets-$50, main bolts I haven’t priced lately but you get the idea. This will cost time and money- but not like it requires 2 months and $1,500 additional.
Adding in more money for further improvements is case by case. Mine is over the top but I’m an old picky guy that has always wanted one done this way. If I could have afforded it, it would have been done long ago but other things take economic precedence.
Idk- maybe someone here is an insurance statistics person and can show the math how it’s only worth an additional $127.31 on top of an $8k engine to be worth the risk.
But my experience says do it.
I get hassles for “the sky is falling” but look where I am. New optimizer- spun cam bearing. Fix that and put together adding a factory designed turbo and buying “save” $25 buy getting glow plugs online instead of napa or dealership = destroyed piston.
I grew up and lived most of my life in Vegas. I understand odds. I see it as newr crazy to not do this - that why I tell everyone to do it.
If you had it as a factory option- $8k for the generic mass production engine or an additional 10% cost for a hand built one that will run smoother and improve lifespan & mpg - would you do it?
