Well guys I have had my 6.5 for 8yrs now and I just found I have coolant starting to get back into my oil. What really hurts is the truck is immaculate and pampered. I got the motor rebuilt professionally in 2003 cause it broke an xhaust valve so I figured I would do it right. Well, I have been getting pressure in my resevoir intermittently now for about 4mths. I just had my truck at the local diesel shop (Vimy Diesel) and we were diagnosing some injection issues when we discovered some antifreeze in the oil. I truly thought I could be one guy who could speak highly for the 6.5 motor but I trully beleive these motors are the worst design. There I am done venting i'm sure I am going to get thrashed for this thread. I have gotton compliments on how this truck pulls by other diesel heads and how it looks but now it is being sold.:(

Drekh happens, bud. Now... is it gaskets, block, crack in head ...?

Howz antifreeze? remember that REAL cold spell we just had?

No reason for block to crack unless you been romping it or unless the thing froze solid in the -40 days...

so why did it go now?

Unless you have low antifreeze, it sure sounds like a head gasket, and that's no big deal. I peeked in your garage, and it's a nice looking truck... well worth putting a new gasket in it.

You should at least get it properly diagnosed. Then you can make the decision to dispose or fix. There not worth much not running.

6.5 ER do not jump ship yet, why not post some details about the truck in your signature. Folks here on this board have "resurrected" many a "junk" 6.5 from the dead and turned people into believers of the 6.5, depending on vintage of vehicle and way you drive or previous owner drove it has a lot of impact on longevity, it is very possible yours is a easy head gasket & bolt swap.

Do you know if head bolts at last job were replaced, if not I suspect there is your problem, head bolts for the 6.5 are 1 time use TTY only bolts. You can do a head gasket swap yourself easily, we can walk you through it, may even have a picture or two.

At a minimum pull the heads anyay just to see if your problem is gasket issue, or bigger problem, (get out your digital camera) post pics as you go and we can get you through it. worst case scenario you need a new engine $3500-5000 vs new truck payment or buying another "used but good truck" with it's own "history". "Don't give up the ship" as we used to say in USN, let us as a group figure out if it is really DOA and can't be brought back.

In the eight years that the new engine has been in there, have you changed the coolant at least three times since it was put in? Green coolant is supposed to be changed every two years, to keep the corosion benefits up to par. If you haven't been changing it every two years, your head gaskets may have been coroding away.

Yah I put in dexcool when I did the motor. I spent 7000 on the motor. I spent 1500 getting my gm dealer to pull it and install/set it up. I have a good relationship with the mechanic there and he knows how I like my stuff to be set up. I had all parts magnufluxed when it was rebuilt. Yes absolutely the head bolts were replaced. What blew me away is how much these motors are out of balance from factory.. You should have seen all the liitle drill holes he had on the flywheel, crank, and connecting rods to bring the motor into balance. He also decked the block/heads. Beleive me when I say this truck is not bagged but if anything over maintanined with oil changes, fuel filters etc. The truck is never cold started and always been an awesome starter. It is always warmed up etc and idled before shutdown. I was planning on trying the gm coolant tablets just to see if it helps. What also ticks me off is the fuel problems I just started haveing. The truck starts quick but hestitates and bucks for 10-20sec. The fuel shop specializes in 6.5's and they are stumped. They have tested everything and that last resort it to try another injection pump to see if that helps. They tried injectors, pmd, crank case sensor, changed oring on fuel shut off solenoid. I don't know what is left. They said my closure time is abnormally high above 2. What do u guys think???? oh and there is only 90000km on the rebuild

We still don't know year of the truck, S or F info, etc. which would help us hazzard a guess, any codes associated with bucking ??? Closure time above 2 isn't good, IIRC Stanadyne bench spec max is 1.92ms but that may be a symptom rather than actual fault.

Hey TD would my reflashed ECM cause issues with the rough idle. When the truck does this it is when the truck has sat for a little while like 20min or so. When it starts u could swear it is a couple of burnt out gp's. It smokes blue/white and is definitly fuel. I have tried giving it throttle while this is happening and it doesn't help at all.

Possibly , is it more pronounced on cold morning, possibly the timing is too far advanced a little, did you try to do a TDC offset or time set after the reflash install , stored TDC may not be happy with physical position of the IP

Hey your sig says set up as a F, so I'm assuming you were originally set up as a S truck, what VIN did you supply for the reflash, if they reflashed it as a S but you aren't running as a S, MAF sensor is still active looking for input as well as EGR inputs, they may have dumbed down the codes to not alarm, but if they did not reflash as a F VIN truck, that may be your problem. Do you have access to a scan tool to see what VIN they set your reflash to.

When it starts u could swear it is a couple of burnt out gp's
There probably is a few burnt out glows. What do you mean in your sig "Has no wastegate" thats not good, we found out, through CR what happens when you run full boost in a 6.5.

What do you mean in your sig "Has no wastegate" thats not good, we found out, through CR what happens when you run full boost in a 6.5.

Yeah, poor guy that Cow Racer.....:D

I have been running this ECM since 2001 with no issues at all. The reflash is based on a 97 F HD program, but my stock ecm was also reflashed by gm to F programing. I built my own homemade wastegate. I am a believer in eliminating crap that is flaky (vac pump etc) at the best of times and making it as mechanically reliable as possible. As far as gp's are concerned I have tested them about half dozen times and they are all perfect actually they are brand new as well. I talked to Edmonton Freightliner and I am going to get an oil analysis done to prove or disprove coolant in my oil. The fuel shop said when they removed the oil fill tube when working on the ip there was a slight sludge build up and they did the taste test and said it was glycol. Of course they called me and I pretty much freaked out. I have not seen any signs of antifreeze in the oil other than dealing with some coolant pressure issues at the reservoir. I have not seen the sludge yet as I am suppose to get the truck today. They were suppose to keep a sample of the sludge for me.

I lost faith in the 6.5 myself, but its like a woman, very hard to leave her.... Matter of fact, i left my wife and have 2 of these things and another with the Cummins in it.... lol

It's hard to beleive with the money we have thrown at these trucks and nobody had admitted to outright burning them and collecting the money. I am very attached to this truck as I love the old body style and I like the cakkle of the 6.5. It is no dmax but it is an excellent truck for what it was built and is used for. If I decide to do some work on this thing where is a good shop to get hi performance stuff such quality head gaskets and studs. CR u have some connections in your area as I am only 2hrs from your area.

I prefer science over someones tongue. Get a sample and send it off before you lose faith. Have they checked the wiring harness? harness for GP's can go bad and make it feel like gp's are bad, even with new ones in. I have been there. Stick a test light in the end and ground the other. I have gone through two of the harnesses on two differant trucks.

Just my two cents.

Tony

Maybe your expectations are set too high, this is/was as designed light duty Diesel so far I have nothing but praise for mine, does all I need it to do & then some. Stuff I have added is stuff GM should have done from day 1 but they moved on with a different approach where in technology now allows for emissions & power gains not ever imagined back in the day.

Beauty of the 6.5 90% of what needs to be done to fix them can be done yourself, parts are plentiful and inxepensive compared to what is powering the newer stuff.

Parts are much cheaper than any of the newer stuff. NO truck payment so if something breaks it's easier to fix it than spend $450 60 times.;) Heck if something went majorly wrong I think I would spend $6,000 on a new drop in engine instead of getting into long drug out payments again. the body is in great shape and this truck does all I need it to do.

>Beauty of the 6.5 90% of what needs to be done to fix them can be done yourself, parts are plentiful and inxepensive compared to what is powering the newer stuff.<

Amen!!!

The 6.5 maybe a little on the weak side in order to outlive the rest of the truck but the duramax is a little on the excessive side. My truck was 26000$C new or about 20000us$ at the time, now a new engine for a duramax I have heard runs around 20000C$(don't know if this is true or not). 90% of the trucks I see on the road don't need 330hp there just used as little more than a grocery getter. Whats going to happen in a few years when your 8 or 10 year old truck needs a new duramax, I don't know if I'd be willing to spend the $ to fix it.

They will be cheaper by then. Once the new Ultrabucks comes out.

just saw a duracrax go on ebay for $3000.00, complete ecm and all.

The 6.5 maybe a little on the weak side in order to outlive the rest of the truck but the duramax is a little on the excessive side. My truck was 26000$C new or about 20000us$ at the time, now a new engine for a duramax I have heard runs around 20000C$(don't know if this is true or not). 90% of the trucks I see on the road don't need 330hp there just used as little more than a grocery getter. Whats going to happen in a few years when your 8 or 10 year old truck needs a new duramax, I don't know if I'd be willing to spend the $ to fix it.