• Welcome to The Truck Stop! We see you haven't REGISTERED yet.

    Your truck knowledge is missing!
    • Registration is FREE , all we need is your birthday and email. (We don't share ANY data with ANYONE)
    • We have tons of knowledge here for your diesel truck!
    • Post your own topics and reply to existing threads to help others out!
    • NO ADS! The site is fully functional and ad free!
    CLICK HERE TO REGISTER!

    Problems registering? Click here to contact us!

    Already registered, but need a PASSWORD RESET? CLICK HERE TO RESET YOUR PASSWORD!

Is there a typical range for a 6.5 between rebuilds?

Sentinelist

Active Member
Messages
145
Reaction score
44
Location
North Texas
Mine has 280k on the clock and I don't think it's ever been rebuilt, though the trans has. It runs great, but as I build it up to take my family into the backwoods for camping, I keep wondering about this. There's always the risk of course, but some expectations are better than rolling the dice. Thanks!
 
If it is running well with those miles, I wouldn't worry. Newer vehicles usually break with no notice.

Get gauges and drive by them, tranny, boost and EGT. A fuel pressure gauge is handy as well.
 
Anywhere between 0 and 1,000,000. there really is no set mileage when you should consider rebuilding any engine. It all boils down to engine health, how it is maintained, and the luck of the draw.
 
x2 if it aint broke dont fix it. Most either die from crank snap, block failure, cracked head, bad head gasket, or a combo of all before they actually wear out. Maintenence is key along with alot of luck. Good injectors, low boost/good flowing exhaust (including turbo), and gauges will let things live as long as possible.
 
Fluidampr time! ;)

it all depends on maintenance, my 140K rig is wore out and needs rebuilt or replaced, and my 255K rig is in good shape. dad just bought a 78K miled 96 and i have never seen a more beat pickup in those miles. has some blowby too.

I would see how much blowby and oil consumption it has, and if its low, I would Fluidampr it, put a big exhaust and turbo on, and just put it on a good preventive maintenance program.

I try to do the Fluidampr and preventive maint. route first.
 
Compression check and oil anaylisis.

Thanks for the tips, guys- that's what I need. Leroy- your exhaust and ATT still have yet to go on but am hoping they will here in the next few weeks! Really looking forward to it. Btw, it's had recent injectors, but the truck isn't modded, and I don't plan to beyond the ATT and exhaust- stuff that makes sense. I've been told marine injectors will let me outdrag newer Duramax rigs. Awesome! But unnecessary.

I'm also of the "if it ain't broke don't fix it" school, and so was the previous owner. He planned to rebuild it, then realized, why? Maintenance won't be a problem for me- it's time that is the issue.
 
The quickest way to kill the engine is run it over the 210 mark on the ECT gauge. Easy to do with the likely 20+ year old fan clutch bolted to that worthless 6 blade excuse for a gas engine fan. Fan clutches loose 200 RPM per year and need to be replaced at 5 years old. The factory type clutch with the undersized fan overheats and gives up when it is needed most climbing a grade.

Somewhere around 200K some folks have head gasket issues. The mains crack in the block and can give way - totally luck of the draw as to when. The 6.5 was redesigned to eliminate these cracking flaws for the military. Only available in an expensive new casting engine.

For those of us with a budget when you do find the last mile in the engine - A military surplus take out 6.2 with less than 30K on it is a $1200 option. With head studs, new rings, and some other things you drop it in for ~$2000 yourself.

With cooling improvements like a clean once a year cooling stack, 9 blade steel fan from a 1998 or use a 2002 Duramax fan, Kennedy Diesel low temp fan clutch (Or HD Hayden clutch from a 1998), 180 "single" T-stat, High Output water pump from a 1998, and A Team Turbo you will add life to the engine. Yes, ATT is under cooling improvement as there is less heat kept in the engine via a plugged exhaust!

Another quick death is from old injectors. They need to be replaced with good ones around 100K miles. If they fail the entire engine and oil cooler goes with it as part of a complete replacement.
 
The quickest way to kill the engine is run it over the 210 mark on the ECT gauge. Easy to do with the likely 20+ year old fan clutch bolted to that worthless 6 blade excuse for a gas engine fan. Fan clutches loose 200 RPM per year and need to be replaced at 5 years old. The factory type clutch with the undersized fan overheats and gives up when it is needed most climbing a grade.

Somewhere around 200K some folks have head gasket issues. The mains crack in the block and can give way - totally luck of the draw as to when. The 6.5 was redesigned to eliminate these cracking flaws for the military. Only available in an expensive new casting engine.

For those of us with a budget when you do find the last mile in the engine - A military surplus take out 6.2 with less than 30K on it is a $1200 option. With head studs, new rings, and some other things you drop it in for ~$2000 yourself.

With cooling improvements like a clean once a year cooling stack, 9 blade steel fan from a 1998 or use a 2002 Duramax fan, Kennedy Diesel low temp fan clutch (Or HD Hayden clutch from a 1998), 180 "single" T-stat, High Output water pump from a 1998, and A Team Turbo you will add life to the engine. Yes, ATT is under cooling improvement as there is less heat kept in the engine via a plugged exhaust!

Another quick death is from old injectors. They need to be replaced with good ones around 100K miles. If they fail the entire engine and oil cooler goes with it as part of a complete replacement.
War-wagon has experience in breaking 6.5's.
Don't believe everything he says......The guy can break an anvil:hihi:
 
x2 on keeping these guys cool. Anything and everything you can do to keep the temps down adds life. If you have not already done this make sure remove the grill and clean behind the trans cooler, oil cooler, and between the condenser and radiator. Leaves and crud get packed behind there over the years. It is amazing just how much crud you can find. I usually vacuum, then blow everything out with compressed air, and finally flush with water. If it really nasty you may have to use oven cleaner.
 
93 is the better block so at least you have that going for you but they can all crack, my 84 engine is cracked, :(

If your really worried, drop the pan and have a look. If it is, then get a used GEP engine off Ebay, Teds Trucks or hit up your core place, I found a GEP shortblock for $500.
 
Let me ask you what is the objective of the rebuild and why do you want to rebuild it???

You don't rebuild just for the sake of rebuilding. LOL!!!
Unless you like to have projects and have unlimited resources: money and time and freedom.

If the answer is to get better reliability, no way.
Those new parts are probably worst than your worn out part inside the truck.

Also in TX, things does not get worn out as fast.
Not too often we have salt on the road.

Maintain it good and it will last a long time.
Fix it when it breaks.

JMHO.
 
Back
Top