6.5 Block Cracking Poll - Voting Concluded [Archive]

Dvldog 8793

01-25-2005, 04:04

Howdy
About 6 months ago my 1999(138,000m) 3500 6.5 started sucking up antifreeze at the rate of about 1gal per 100miles. Due mostly to info from this board I determined that it was most likely a cracked block and even if it wasn't, the engine should come out to properly fix whatever it was. Removeing the engine was much easier than I thought, again with direct help from this board and it's members. As I was pulling the pan, my 6yr old girl was the first to say "I see the crack!!!" Needless to say in my mind it was HUGE. It started in the piston oiler hole in the number 3 web, went completly through and up into #6 & #8 cylinders about 2 inches. This crack had a shift of about 1/32 inch while the mains were still bolted on. This was the 599 block and by everything that I've been able to find should NOT have had large piston oilers, it did. When I started looking for long blocks I found the cheapest GM block at a dealer about 200 miles away, so off went the check and home came the block. All total w/ tax ws about $6200. When I was ordering all the "misc parts" at my LOCAL dealer he asked if I had tried warrenty for the old motor. The truck was about 40,000 miles out of warrenty but what the heck I called GM and started a file. They told me that I had to get the problem "verified" at a dealership. Well my engine was in pieces all over my shop, so I took the bare block to my dealer in the trunk of my car. the service guy didn't even touch it, he looked and said "Yep it's cracked" and home I went. 5 days later a call from GM customer service told me that the General was willing to stand behind the block with 30% of the cost of the engine. I was amazed! As it turns out the dealership had recommended they pay for 100% of the parts.
I have waited until I got the check to write this post as I was still unsure that they would pay-up. Got it on Friday.
I had done all the work.I am a "shade-tree" at BEST.
I bought the parts from a different dealer.
They "Verified" an unknown block.
They stood behind me 110%
This is the 3rd time this dealer has done this for me, 1st-turbo, 2cnd-IP. both out of warrenty and replaced for free.
I have never bought a vehicle from this dealer.
I'm wrtting this long-winded story just because I think when someone does it right people should know. I took some of that check and got the service dept pizza for lunch(they can't drink beer at work ) Not all dealer experiences are bad. GM customer service still swears that the reason they gave me anything was because this is such a RARE problem, "those blocks never break!" So between selling off some of the old parts and the check from GM I have a new AM GENERAL long block with 3yr/50k warrenty for about $2500. Plus my labor but it was a good learning experience and I got to replace/upgrade many things in the process.
If I can help anyone out in this area let me know.
L8r
Conley Janssen

eracers999

01-25-2005, 06:12

The mains in this block were broken all on the 1 3 5 7 side, the 2nd main cracked from the outer bolt hole, curled under the recess, then angled up to the cam bearing. 3rd main broke the mounting section clear out of the block, witch gave me a look at how much of contact or surface area is actually holding it together, let me say, not very much. And 4th main pretty much the same story as no2. Wierd because the 2 4 6 8 side all had loosened bent and broken main bolts, but no cracks. Crank had a big ole crack in it, im shure from the block letting it over flex. All bearings looked real good. Did'nt have any coolant loss, had good oil psi,45 hot down the road, runnin so good that 2 weeks prior to my discovery i said that it is getting ready to blow up. How i found all this mess was that i had purchased a main gurdle kit from DSG, i pulled the front drive unit out and the oil pan down, only to discover that, thats all she wrote. I will have my new project performance build in and running next week. Magged and crack free original block with Splayed mains, (Kennedy caps and Cameron Racing Engines doing the machine work) With std main bearings. Will attempt stud gurdle install with splayed mains. Mahle pistons cut down .030 to make 18:1 compression, ceramic coated tops and coated sides ( Calico coatings ) .020 over pistons, fully balanced assembly, ( the pistons were 6 grams off from hi to lo when weighed up) with std std crank, all 8 rods reworked, new by pass valves in block, 98 oil pump, phazer gear drive, 98 cooling. (heads were crack free can you believe that) ARP head stud kit. 8 new diamond pre cups. Did porting on the upper and lower intake plenums, ported the lower section of the exhaust housing. Of coarse there is all the other boring details of nickle dime stuff that was done, anything it needed it got. We will see how this holds up. Check out the pics. On edit / Engine had 73k on a us diesel rebuild that the owner before me had installed. I bought it with around 35k on it and at that time it had blo by (strong). Looking back at the maint records showed that it had a boost sensor failure twice in that time, the first 35k. I think that it was burned down then. Rings were flaking badly, timing chain beyond loose, rear main installed as crooked as can be, front seal damaged. This engine looked like it was assembled with used parts, i guess you would have to see it.

Kent

http://client.webshots.com/photo/252462408/252478840gpUPBv

[ 01-25-2005, 09:00 PM: Message edited by: Kent ]

cruzer

01-25-2005, 08:42

So you can't view the results unless you vote, and
you can't vote if you're block hasn't cracked.

Ronnie, maybe a 1st question should be did you're block crack? How many miles you have on it?

Might be able to come up w/a percentage of failure to non-failure. Is'nt there approx 10,000+ members? Not real scientific but could get some amunition for GM.

Just a thought, Ken

Kennedy

01-25-2005, 13:09

The mileage range could be tweaked some. It would be interesting to find out how far past 100k the failures occurred. I have heard of quite a few in the 100-120 range which is just out of waranty...

rjschoolcraft

01-25-2005, 13:45

Unfortunately, I cannot edit the poll after it has been posted. If you have gone past 100K before cracking, please post the mileage in this thread.

Mine was 158,500 miles. Came down for a broken #8 piston, but would have really grenaded before much longer! :eek:

jdmetcalf57

01-25-2005, 18:53

I found the problem at 97K although in retrospect I had been losing a small amount of coolant for 6mo. Cracked straight up front of cyl wall # 3. Still fighting with GM over warranty coverage. I have had this truck for 40k miles and it looked like new when I bought it so I don't think the previous owner abused it. I pull a 4K hilo type camper and I baby it. I seldom use over 1/2 to 2/3 throttle. I was planning on driving this engine to 200K plus like I have many other gassers.

jdmetcalf57

01-26-2005, 03:46

ronniejoe;
It dawned on me that a lot of people that have had the cracked block problem probably have moved on to the duramax and don't read this colum. It would be good to post in that forum to get those people to contribute to this poll.

jbplock

01-26-2005, 08:57

I just saw ronniejoe's post in the Duramax forum and came over to take the survey.

I sold my 98 K3500 with about 65kmi in Oct 2002 and bought a new 03 Duramax. I had put on gauges and a banks down pipe but no other performance mods. I had a few minor problems with the 98 (leaky oil cooler lines, valve cover oil leak & lift pump) but it was running great when I sold it. I bought it with 29kmi in 1999 and used it to tow a 6k 5th wheel about 30% of the time. The previous owner also used it for towing a 5th wheel. I know the person I sold it to also used it for some light towing.

Recently I received a call from the truck's current owner. He had just bought the truck with a little over 100kmi from a used car dealer and the truck was using coolant. He had taken it back to the dealer who then took it to a local Chevy garage. The GM tech first diagnosed the problem as warped head and head gasket. They machined the head and after the repair it was still using coolant. After hearing his story I referred him to TheDieselPage 6.5 forum and told him it sounded like a cracked block. He took the truck back again and the dealer retuned it to the Chevy garage. The GM tech tore down the engine and confirmed it was a cracked block. The new owner ended up splitting the cost of a new (or reman?) long block with the dealer he bought it from.
Last I heard it was running well.
smile.gif

[ 01-26-2005, 08:07 AM: Message edited by: jbplock ]

ace58

01-26-2005, 18:10

I have a 1999 K1500 Chevy Suburban that had 150,250 miles when the crack was discovered. It started using anti-freeze at the rate of about 250 miles to the gallon. After the second gallon, it was light use until I had a chance to replace the head gaskets, or so I thought.
I am fortunate to have a friend in between jobs, with an empty garage, that has been a motorcycle, car, and truck mechanic. He was anxious to get the project, and removed the drivers side head. The gasket was fine but with all the sludge it was decided to pull the engine, hot tank, re-ring and replace gaskets. The truck is exceptionally clean and has been garaged since new, so how bad could it be?
When the engine was on the stand the crack could not be seen until the crank was removed. Once exposed, it seemed more like a ravine. I have never seen an engine crack like it. It starts in the 2nd main web and extends up into the cylinder bore. I am glad Kevin suggested the freshening up project, or it would have been uglier.
I have a friend who is a Chevy parts manager locally that tried to locate parts reasonably, to no avail. I put the word out of my situation, and oddly enough a co-worker of a friend that I drag raced with knew of a GM tech at another dealership that ran GM diesels who had an engine. It was out of a G series truck, that had an oil leak in the block above the oil filter boss discovered at 300 miles. GM authorized a replacement motor, and the tech kept the motor. He also had 2 low mileage cylinder heads from a C/K series, bought the gasket set, assembled everything and even delivered to Kevins garage for $1500.
That is when I decided to due the performance upgrades I have been reading about (gauges, exhaust, crossover pipe, intercooler, turbo, IP, injectors, etc.)first, with Jim Begley's build up and show down and then everyone here. All the knowledge that is shared here has been a blessing, and this project could have never happened without it. Finally, I brought the truck to the tech I bought the engine from today to get it timed, with John Kennedy's instructions.

Mainous

01-26-2005, 18:53

Mine cracked at 135K miles. The only upgrade I had made at the time was downpipe and exhaust. I bought the truck with 72K miles on it and the miles I put on it were mostly empty highway miles.
I want to mention that my truck had an odd engine knock from the time I bought it. Having had a 92 Chev with 6.5 before this one, I noticed the knock but the truck ran fine. Anyone else notice this? Anyway, my symptoms were the normal coolant usage.
I hate to admit it but I just bought a 99 Suburban w/6.5 for my wife. I will likely install the stud girdle right away and pull the pan right before the warranty expires.

rjschoolcraft

01-27-2005, 04:20

I've added a post to make it possible to view the results without voting.

MartyB

01-27-2005, 16:57

I was at 103k Miles when the engine tanked. It would be interesting to see the number splits past 100K, I would swag from posts on here, 120-150K would be the norm. Altho 100-130K would not surise me either.

patrick m.

01-29-2005, 09:59

i wonder what is the ratio of members who have had cracked blocks to those who have not

eracers999

01-29-2005, 21:33

I am also wondering if anyone has had problems after the stud stabilizer install??

Kent

humding

01-30-2005, 14:46

My 6.2 installed in a Land Rover 110 has three cracked main webs at the moment. I was looking at putting in a 6.5 NA or Turbo but this thread is making me think again. As much as I dislike it it looks like a standard Land Rover engine is going to be more reliable. Is there anything that can be done, checked, certain blocks etc that can prevent this problem. Being based in Ireland where spares are unobtainable I need something that is going to be reliable for the long haul.

BETA

01-31-2005, 04:47

HUMDING!

I can get you a new GEP SB engine, and you should, more than likely, be doing OK.

Shipping from Sweden to Ireland is 270 EUR.

BETA

humding

02-02-2005, 15:55

What exactly is a GEP SB?

rjschoolcraft

02-02-2005, 16:48

General Engine Products Short Block. ;)

BETA

02-03-2005, 00:44

Originally posted by humding:
What exactly is a GEP SB? HUMDING!

Here are some information regarding the GEP-HUMMER engines.

They are heavily reinforced compared to GM production. Blocks are cast in a molybdenum alloy with 25% increased tensile strength. More material and more generous fillets further strengthen the block. The oil injection nozzles, for piston cooling, are repositioned so they don

jspringator

02-03-2005, 10:01

Does a GEP block preclude the need for splayed main caps?

K2500

02-03-2005, 22:55

Cracked block @ 220K New jasper, running great

BETA

02-04-2005, 02:31

Originally posted by James Springate:
Does a GEP block preclude the need for splayed main caps? GEP have reengineerd the GM 6.5. The block material is not only stronger (higher tensile strength) but also more ductile. Actually, all material properties have improved. Caps and bulkheads are wider. To my knowledge, no cracking, or any other problem, have been reported.

We have only sold approx. 50 engines over a 9 month period, and so fare we are very pleased with them.

jkpyper

02-07-2005, 09:29

Well, this is blown engine #2 for me. It first went around 86K and GM kindly replaced it with a new long block free of charge. The dealer mechanic was even kind enough to remove the timing gear/Phazer and hi-flow injectors from my old engine and intall them on the new engine. Now at 125K (39K since the swap) I am looking at another long block swap. I was starting to think the cracks were due to my "excessive" tweaking of the engine ( hi-flow injectors, boost increase, timing gear/Phazer) but after seeing the results of the survey, I'm not convinced that is the primary cause. Seeing that 61% of respondants had box-stock engines makes me think that tweaking has little effect on the durability of the engine. It seems to be luck of the draw.

Lets hope the new castings hold up better.

-JKP

Kennedy

02-08-2005, 07:57

My opinion is that nothing short of improving the rigidity will help. The splayed cap center mains are the next best thing to a deep skirt block which is what this should have been in the first place. Of course evolving from the "economical" 6.2 platform, this was not practical.

BETA

02-08-2005, 10:09

This is a copy of a mail to GM:

"At only 28,000 km (17,400 miles) the #2 and #4 bulkheads have cracked right through the piston oil spray nozzle feed holes. Cracks go up into cylinder bores on each side of the bulkheads - totally 4 bores. Coolant leaks into the oil sump. The truck has been perfectly maintained and served. Engine block heater has always been used when the temperature is below +10 degrees C. Has always been fully warmed up before driving. Has never towed. Any suggestions why this has happened? Is there any way that I will get help from you with the repair bill? Pictures showing the cracks are attached."

This is GM's only reply, I never heard back from them. I did mail 3-4 reminders and then I gave up.

cac@chevrolet.com
den 10 juli 2002 21:52
We Received Your Message

"Thank you for your e-mail to Chevrolet. We appreciate hearing from all of our current and future customers!

Our representatives normally respond to e-mail messages within 24 hours, excluding weekends and holidays. Occasionally, however, we may experience higher volumes of e-mail messages. This may create a delay in our response to you.

Rest assured, we will answer your message in the shortest time possible. If you are a current Chevrolet owner and are in need of immediate assistance, you may also call 800-222-1020 from 8:00 a.m. to 11:00 p.m. EST, Monday through Friday.

Thank you for your interest in Chevrolet!

Chevrolet Division"

www.thedieselpage.com/images/betacrack01.jpg (http://www.thedieselpage.com/images/betacrack01.jpg)
www.thedieselpage.com/images/betacrack02.jpg (http://www.thedieselpage.com/images/betacrack02.jpg)
www.thedieselpage.com/images/betacrack03.jpg (http://www.thedieselpage.com/images/betacrack03.jpg)
www.thedieselpage.com/images/betacrack04.jpg (http://www.thedieselpage.com/images/betacrack04.jpg)

[ 02-08-2005, 09:20 AM: Message edited by: BETA ]

humding

02-08-2005, 15:32

Thanks for the info. I have decided to go with a customised 6.2 from the diesel depot, mainly because I know of a few running in England without any difficulties. Anyway Beta what sort of money would your version be?

Schuylkill-trans

02-14-2005, 05:13

We have 16 6.5 diesels.Most are 2000,s. Oil analysis shows anti freeze in 14 of them.Not enough for the eye to see, but your results will show.We are constantly working on these engines.Either the heads crack,or the gasket leaks.Some have had web cracking.The lifters have come apart in most and some up to three times.The most mileage on any is usually between 75,000 & 120,000.I heard that the 99 cast blocks were prone to web cracking.GM is finally working with us as three are down right now.Also four different chevy dealers have worked on these motors and never mentioned anti freeze in the oil. Analysis is the only way to tell.I strongly suggest you get in a program.

redrider

02-20-2005, 20:33

My 97 3500 6.5 had 153000 on it when the crank broke,right behind #3 main.webbing on #3 was broke out of the block.It appears it had been crack for awhile,because the crack was polished from rubbing.I was not losing any coolant and had 40lbs of oil pressure.when I pulled what was left of the crank out I pull a piece of the main web out that was about 3 inches long.I found a 599 block and have put kennedys splade mains in aand should have it back together next weekend. I HOPE

jkpyper

03-03-2005, 05:41

I dropped the engine last night and pulled the pan. My preliminary inspection reveals cracks between #3 and #5 cylinder and between #5 and #7. I didn't get a good look at the other side yet, but I am pretty positive there will be a crack between #6 and #8. The cracks start at the oil spray holes and migrate right up the cylinder wall. My modifications include moderate boost (12 psi) and moderate fuel increase (hi-flow injectors) and -1.58 TDC learn. I'll add more if I find anything else.

arveetek

03-05-2005, 14:56

I know it's not a 6.5L, but I thought ya'll might be interested to know that my '82 model red block 6.2L shows no signs of cracks anywhere. I've put 120K miles on it since I overhauled it 9 years ago. I just re-ringed it and installed new bearings, injectors, etc. then. I pulled it last week for some maintenance and upgrades, and really inspected it. This engine has been worked HARD. I know it doesn't produce the power levels some of your 6.5L's do, but it's probably close, with a cranked-up IP and turbocharger (14 psi boost pressure), and 4" exhaust. I've towed my 8500 lb 5th-wheel to Florida, Ohio, and recently to Colorado. I've seen the EGT's spike past 1400 when running n/a, but never above 1050 after installing the turbo.

It's been stated that the '82 red blocks had a higher nickel content than later 6.2L and 6.5L engines. I'm beginning to believe it. I have yet to hear of any confirmed cracked '82 blocks. Later 6.2L blocks have cracked and busted just like the 6.5L.

I haven't had any major problems whatsoever in the last 9 years I've driven this 6.2L. It just lately started smoking a lot on startup, and then smoking a little after being warmed up, and I found tapered cylinder walls, a broken compression ring, and worn out timing chain.

I have my block at the machine shop right now. It's been decked and bored .030" over, and Benny Avant is going to make me some custom ceramic-coated pistons to replace the stock pistons that were starting to show signs of some serious heat damage. I'm also installing a DSG gear drive and stud girdle kit while I'm at it. Hope to have an even better running engine than before, and one that will last!

Just thought you might be interested.

Casey

ogrice

04-14-2005, 12:58

The original 6.5 in my c3500 dually started eating about 1 gal of coolant every 100 miles. This started happening at around 200k. I'm glad that I got that kind of miles out of my truck, unlike some others that were cracked at around 120-130k. When I yanked out the engine and disassembled it the 3,5,7 cylinders were cracked.
Once the pistons were out anyone could look into the cylinder bore and see the cracks plain as day. I suspect that the cracks were probably there long before I had the high consumption of coolant.
The coolant symptom didn't start until after I had let other people use my truck. My brothers friend had told me that he had to put fluid in the radiator because the low coolant light came in. At that time I was driving my other car to work and he was using the truck. He had been using my truck to go to work or the last three months. I thought "no problem, his work is only 8 miles away and all sidestreets." I asked him how many times he has had to add coolant, he said four times in the last three months. I took the truck away from him and told him to find another way to get to work. My radiator leaked a little bit, but after he said that, I knew there was a big problem.
Funny how you always seem to get your rig back in totally different shape after someone else uses it.

99gmccrew

04-21-2005, 20:49

What is the reason that the 99's seem to be cracking at a higher rate than other years?

99gmccrew

99gmccrew

04-30-2005, 15:04

I reseached my own question and found out from an older post by mainous, the reason for the blocks cracking and also learned that I have the "enhanced block". I Feel Better now. :cool:

Hansh

05-29-2005, 17:05

Pulled my engine due to a cracked piston, mains also cracked. It was a Jasper rebuild with about 110k on it, truck has about 240k. It is a 1993 K3500, 6.5TD, I had it for about 70k. While under my ownership, it did not see hard use, (I have been told I drive like a grandma!)occasional towing of a boat and car trailer, and I never overheated it. I guess either a GEP or rebuild is due...!!!!

raypete

06-22-2005, 14:46

I now have a Jasper engine replacing the original which had a crack in #3 cylinder wall. General Motors said they would cover if crack was in main bearing area but not if in cylinder wall. We were at 69000 miles.

Hansh

06-23-2005, 06:07

Raypete, make sure you are getting the new block and ALL new parts. I went with Peninsular Engine over in Michigan. Great to work with. I highly recommend them. Their engines come direct from GEP. I got the 18:1 and added the 97 cooling. Mine is in the truck and I hope to have most of my engine back together Friday and fire her up next week.

brian5003

06-27-2005, 10:34

mine cracked all the mains up to the cam shaft...it had 130000.....and im done. I will never own another. Chevy sucks! I'm going to buy a honda.

Chuck1

06-27-2005, 22:28

Air helps I have a 94 td L56 and I replaced the stock air filter with a K@N hopeing to get more power. I may have got a little I couldn,t really tell much . But I just drilled out the Air intake and blocked off the EGR and man its night and day . This has really made a big difference.I just wonder if my EGR has been leaking all this time .It was unpluged

trbankii

08-26-2005, 09:54

One of the posts early on suggested an option for "no cracks" to try to determine what percentage of members have dealt with problems with cracks. I understand that the poll cannot be changed, but could another one be started with the basic question of whether you have had cracks or not? Seems like it would help to get a feel for the extent of the problem.

I tried to post a poll, but found I don't have the authority to do so.

Slim shady

09-03-2005, 07:29

WELL I HAVE JUST WENT THE ROUNDS LIKE EVRYONE ELSE. I DID A CLUTCH (BIG MONEY) THEN PULLED THE ENGINE WHILE IT WAS OUT BECAUSE IT STARTED TO EAT A LITTLE COOLANT AND HAD MORE BLOWBY THAN WHAT I THOUGHT WAS OK. I HAD 140,000 MILES ON THE TRUCK AND FIGURED I MIGHT AS WELL REBUILD IT , (RE RING AND BEARINGS) WELL ALL OF THE MAINS ARE CRACKED AND THE BLOCK IS JUNK. NOW I HAVE JUST GOT A 6.2 BLOCK WITH A CASTING NUMBER OF 14022660, I AM GOING TO REBUILD IT BECAUSE I DON'T WANT TO GO THROUGH THIS AGAIN.

EVERYONE HERE IN DETROIT LAUGHED WHEN I ASKED THEM ABOUT A GOOD USED 6.5 BLOCK OR ENGINE! EVEN THE GM GUYS, HARD TO HAVE THE FORD GUYS TELL YOU (SHOULD HAVE BOUGHT A FORD)

1995 C2500 4X4 MT8 5 SPD :confused:

rjschoolcraft

01-01-2006, 09:06

The crack poll is now officially over. Some interesting results. We had 49 people vote in the poll. 76% of the blocks (37) made it to 100,000+ miles. 55% (27) were used for medium duty towing. 59% (29) of the failures had coolant usage preceding the crack discovery. The most interesting data in the poll (I think) is that 63% (31) were completely stock. The disappointing statistic is that 86% (42) received no warranty consideration from GM

From this data it seems reasonable to conclude that modification for more power output has little impact on the cracking problem. A bigger indicator seems to be how one uses his truck. 77% of the failures were on trucks doing medium duty or heavy duty towing. My suspicion is that not that many 6.5 owners use their trucks for "heavy duty" towing. It seems that if you "work" your truck, you're more likely to experience a cracked block.

As some of you have suggested, I am planning a new poll to collect some more data to understand this problem better. I'll try to post it soon.

[ 01-01-2006, 12:09 PM: Message edited by: ronniejoe ]

bill lom

01-11-2006, 14:43

looks like i have the same problem using coolant in # 3 cylinder i changed head gasket still leaking so i drained coolant & installed barr's leak-head gasket repair seem ok for now, i know the head gasket was torn up above # 3 cylinder (HAY GM MAYBE YOU CAN EAT THE COST OF THIS POOR MOTOR)

broke down

04-02-2006, 04:22

what is the stud girdle/stabilizer?

signgrafix

04-04-2006, 20:46