Hello,

I have a 1998 chevy 2500 6.5 turbo diesel. The engine is cracked in #8 cylinder, and has main cracks. Block is garbage.

I found a complete 1992 6.2l Diesel motor with 100,000 miles on it, excellent running condition. I was wondering if i can put the 6.2 into my truck?

I know i have to swap the heads, the front timing plate, the electronic ip pump, the timming chain. sensors ect.. Will this engine hold up to the turbo?? I think my turbo is the GM-8??

Will there be any difference in power??

I plan on towing a boat, maybe a car once in a while, just light duty work, and using as a daily driver. Let me know thanks allot

See this thread. http://dieselplace.com/forum/showthread.php?t=155504

See this thread. http://dieselplace.com/forum/showthread.php?t=155504

Checked it out, just wondering if the stock pistons in the 6.2l would hold up to my gm8 turbo, running on stock boost, and if so for how long, and will there be any horsepower torque lost or will it be about the same? I cannot find a 6.5l block anywhere around for a good price.

Frustrating huh!!!! Yeh i've spent alot of hours checking the same thing. I think i'm going to do it. Here is what i found. The blocks are better in the older 6.2's. They had more nickel in the metal and where built beefier. Everything will bolt up from what i found. I'm going to bore it to a 6.5. The turbo won't work as well without this.. The timing cover from the 6.5 will let you run the electric pump on your 98. Here is the list of should buys for it. An upgraded water pump, new oil lines (upgraded ones) and new head bolts. Everything else should be good to go... Let me know if you find out any more too.. I would stay away from the 6.5 block unless you go with the new amg one. Also have your heads checked before you put them on.

Frustrating huh!!!! Yeh i've spent alot of hours checking the same thing. I think i'm going to do it. Here is what i found. The blocks are better in the older 6.2's. They had more nickel in the metal and where built beefier. Everything will bolt up from what i found. I'm going to bore it to a 6.5. The turbo won't work as well without this.. The timing cover from the 6.5 will let you run the electric pump on your 98. Here is the list of should buys for it. An upgraded water pump, new oil lines (upgraded ones) and new head bolts. Everything else should be good to go... Let me know if you find out any more too.. I would stay away from the 6.5 block unless you go with the new amg one. Also have your heads checked before you put them on.

Thanks allot for all the info. I have a full 6.5l turo diesel rebuilt kit compltete with standard size 6.5l pistons. I found a complete motor for around $800, and it would cost $350 for boring, i have rebuilt a few 6.5's but this will be the first 6.2 motor, I think i am going to go for it too. The only thing that I was wondering was if I could run the turbo on the 6.2l pistons both the 6.5l and the 6.2l have 21.3:1 compression but the 6.2l pistons are weaker. I have the high output water pump brand new, and the better cooling crossovers from my 98. I am going to run an intercooler to keep that motor running cooler. The only thing that bugs me is if I can run that 6.2l turbo or will the pistons detonate and destroy the motor. I am planning on running stock boost. The hp levels should be about the same as the 6.5l TD?

Thank allot

Yeh i talked to one guy about it and said that the 6.2 motor might not last long running a turbo on it. He said the pistons are the weak link if you are going to do that. Also he said it was 150hp and the 6.5 is 170hp. Where did you get your rebuild kit and the ho pump. Let me know i'm going to be ordering some stuff this week. Let me know that would be great.

Yeh i talked to one guy about it and said that the 6.2 motor might not last long running a turbo on it. He said the pistons are the weak link if you are going to do that. Also he said it was 150hp and the 6.5 is 170hp. Where did you get your rebuild kit and the ho pump. Let me know i'm going to be ordering some stuff this week. Let me know that would be great.

I got the rebuild kit from: http://cgi.ebay.com/ebaymotors/New-6-5-6-5L-GM-Chevy-Diesel-Engine-Rebuild-Kit_W0QQcmdZViewItemQQcategoryZ33620QQihZ012QQitem Z220110623585QQrdZ1QQsspagenameZWDVW

seems to be a nice guy. The water pump i bought locally from a parts shop, paid $100 for it. I think I am going to bore the 6.2l to a 6.5l for the stock power levels. Locally there is no 6.5l motors for me, there are 6.5l blocks that need .30 or .40 over boring but i am worried they will crack soon because of the high millage, the 6.2l seems like a good way to go because it will take my standard size pistons if i bore to a 6.5l.

Thanks i was looking at that rebuild kit too... Yeh i would go with the 6.2 bored to 6.5. Also look on the kennedy diesel add too. There was a upgrade he had there. Something about endcaps. Supposed to make the block and crank much stronger. Don't know it's another $500. Its under motor parts on the 6.5

Thanks i was looking at that rebuild kit too... Yeh i would go with the 6.2 bored to 6.5. Also look on the kennedy diesel add too. There was a upgrade he had there. Something about endcaps. Supposed to make the block and crank much stronger. Don't know it's another $500. Its under motor parts on the 6.5

Hello,

Thanks will take a look, talked to my loacal machine shop and he said that the only 6.2l he reccomends boring to a 6.5l is the 92+ 599 casting with the thicker walls. I am going to check that motor today before i buy it and make sure its a 599 casting.

Thanks

Yeh i heard stay away from the 80-82 6.2's. The rest should be ok. Let me know how it's going and i'll keep you posted too.

Yeh i heard stay away from the 80-82 6.2's. The rest should be ok. Let me know how it's going and i'll keep you posted too.

Got a 92 599 6.2l diesel motor today, gonna stip it down to the block this week and get it bored to a 6.5l, I think it needs to be bored .80 over to become a standard size 6.5l, about 4 rounds on the boring machine since they can only do about .20 per time. Also get your self the 1 piece rear main seal one. The only thing that might be different is the head gasket might have to be different.

Will the 1 piece rear seal work. Let me know thanks...

Will the 1 piece rear seal work. Let me know thanks...

you'll need the 1 peace rear seal if you are palnning on using your crank.

Thanks

The latest 6.2's were the same casting as the 6.5, just smaller bore.

Yeh i've noticed that. I found one from the late 80's with only 300 miles on it. Can believe it:D . The casting and metal were supposed to be better then too. Yeh i think my 95 6.5 has the 599 cast too.

I was going to leave the crank from the 6.2 in there. Or get a new forged crank. Can i put a 6.5 with the one piece seal in the motor?

crap another question. I'm getting a new water pump. Would i order one for a 95 or the year of the 6.2?

crap another question. I'm getting a new water pump. Would i order one for a 95 or the year of the 6.2?

I'm pretty sure you can throw your crank in there as long as its a 1 peice seal, the water pump you want if for the 95 6.5 or newer because the belt routing on the 6.2l and the 6.5l is different, apparently the 6.5 and 6.2 water pumps spin oposite directions, someone told me.

where did you get he high output water pump? Are you using your old crank from the 6.5. Have you thought about the new forged cranks. There supposed to by 10x better.

Talked with the machine guy today. Didn't know if you can run a 6.2 crank. He might be worried about it being balanced being i'm putting 6.5 pistons. Did your machine guy say anything?

Talked with the machine guy today. Didn't know if you can run a 6.2 crank. He might be worried about it being balanced being i'm putting 6.5 pistons. Did your machine guy say anything?

I'm gonna run the 6.5l crank in there, I just got it polished, the 1992 599 block looks to be identical to the 599 6.5l block, even has the tap drilled out for the turbo oil line feed, it's just pluged with a screw in plug. I think the crank shaft and the connecting rods have the same stroke, so I wouldn't see why not to run the 6.2l crank. Is it a 1 peice seal or the 2 peice rope type seal?

I think it's the 2 piece... Would like the 1 piece... I will see when i get it...

I think it's the 2 piece... Would like the 1 piece... I will see when i get it...

if it's the 2 peice you will have to stick with the 6.2l crank, but you might be able to get everything balanced once it's bored and the crank and pistons are connected

Can you switch it over to a 1 piece. Is that possible. Would like too if i could...

Guys, first let me say that I have no idea how the 6.2L crank and the 6.5L crank are different...but let me tell you what I know about gassers.

A 305 and a 350 Chevy V8 have the same stroke. A 305 crank will fit in a 350 and a 350 crank will fit in a 305. But, you can't actually USE it just because it fits and has the same stroke.

Here is why: A crankshaft is balanced to counteract the weight of the rods and pistons running up and down the cylinder (that's what all those big masses of iron are on the crank, opposite the journals where the rod attaches).

A 6.2 has smaller pistons than a 6.5 and thus, the weight of the rod and piston is lighter than that of a 6.5. So...the 6.2 crank is balanced for 6.2 rods/pistons and the 6.5 is balanced for 6.5 rods and pistons.

If you use a 6.2 crank in a 6.5 you are probably going to get some serious, engine wrecking vibration. The same would happen if you put a 6.5 crank in a 6.2.

Now you COULD use a 6.5 crank in a 6.2 if you had the entire rotating assembly balanced. They do this by drilling out material from those weights on the crank. Thus, the 6.5 crank could have material removed to balance it with 6.2L rods and pistons.

You CAN'T (I suppose you could but it would be expensive) rebalance a 6.2 crank to work with 6.5L rods/pistons because you would have to add material to the crank weights.

My two cents. Good luck.

Well another option... I've read things either way.... Could i keep it a 6.2 and bolt all the 6.5 stuff on the top. Would the turbo eat the pistons or would the turbo work ok...????

Yes that was route I was going with until I opted for trying the new 6.5 Diesel Direct beefy block might want to check with D Cam or Fred482 in 6.2 forum who have done it a couple of times for what is involved with going that route, my 6.2 donor crank was bad so while deciding what to do next the Diesel Direct option became interesting possibility

Truthfully...I have no idea if you would eat the 6.2 for lunch with a turbo.

However, I do know that Banks Power used to have a bolt on kit to turbocharge the 6.2 and it did not come with new pistons. So...you be the judge.

Will work fine quite a few have done it, but probably limit it to GM4-8 non IC boost levels 10 psi or so sustained boost

Hi guys

I've never posted on here before but this is an interesting thread. I have a 1994 1 ton crew cab dually. 4 years ago I bought this truck with a bad motor. I put a 6.2 in it and bolted on all the 6.5 stuff( pump, turbo) etc. I haul a 10.5' lance camper on it and am running stock peak boost of 13 psi. Also have the tdco set at -1.94 and am running the timing at 8.5 degrees. It works just fine. You just need to use your head and watch temps and it will live for quite awhile. Mines doing fine. It was a stock 6.2. Hope this helps you all

Steve

Hi guys

I've never posted on here before but this is an interesting thread. I have a 1994 1 ton crew cab dually. 4 years ago I bought this truck with a bad motor. I put a 6.2 in it and bolted on all the 6.5 stuff( pump, turbo) etc. I haul a 10.5' lance camper on it and am running stock peak boost of 13 psi. Also have the tdco set at -1.94 and am running the timing at 8.5 degrees. It works just fine. You just need to use your head and watch temps and it will live for quite awhile. Mines doing fine. It was a stock 6.2. Hope this helps you all

Steve

Great to see all the opinions. From what I have read you can run the turbo on the 6.2l diesel, just leave it at stock levels, and it should run fine. There was a 10-15hp difference in the 6.2l and 6.5l bores running the turbo. My truck is a 1998 and it has the GM-8 Turbo.

The motor that I have purchased is a 1992 599 6.2l motor complete. It also has the turbo oil feed tap on it already.

Before I rip this motor apart to peices, is it worth boring it to a 6.5L? or just run it as a 6.2L with the 6.5L heads and all the 6.5l sensors and bolt on's.

Will it hold up to the GM-8 Turbo? or will it melt the pistons?

I am planning on running an intercooler on the truck. I have the high output water pump and the dual thermostat crossover.

How much torque would be sacreficed between the 6.2l and 6.5l bore?

If I bored the block to a 6.5L, can i just slap my whole 6.5l rotating assembly into the newly bored 6.2l/6.5l block?

I ran a T3 turbo on my 1997 mazda mx-6 for 2 years now with stock internals, but intercooled, and the thing still runs fine, can't imagine the 6.2L diesel motor having weaker pistons than a little 2.5L V6 car.

The only towing that my truck is going to see is pulling a boat, and pulling a 2000lbs aluminum car hauler with a car on it, once in a while.

I want to do this right from the beginning and at the same time get the truck out on the road.

Machine shop quoted me $350.00 for boring it out to a 6.5l plus cleaning it, and replacing the cam bearings, probably around $500. My old 6.5L block is complete, eveything in it is brand new except the #8 cylinder is shot, and the block has cracks, so the motor is a good donor for the new one.

Thanks allot guys,

This site is great.. Yeh i spoke with a guy who rebuilds 6.2 into 6.5s. He said you are ok either way.. You an use the 6.2 crank and everything or bore it out and either way the balance of the motor is good to go. $350 is a little high for the boring but is he cleaning and washing it all out and putting new soft plugs in for ya.. I got a quote here for $125-$175 for the boring. Yeh i'm at the same road you are in. I'm getting the 6.2 on sat and have to decide to bore or just put the thing in and go... Let me know what you do too....

One purchase everyone said is to get new head bolts... Aftermarket good ones not the torque ones.. Will save your head gaskets and work much better...

This site is great.. Yeh i spoke with a guy who rebuilds 6.2 into 6.5s. He said you are ok either way.. You an use the 6.2 crank and everything or bore it out and either way the balance of the motor is good to go. $350 is a little high for the boring but is he cleaning and washing it all out and putting new soft plugs in for ya.. I got a quote here for $125-$175 for the boring. Yeh i'm at the same road you are in. I'm getting the 6.2 on sat and have to decide to bore or just put the thing in and go... Let me know what you do too....

One purchase everyone said is to get new head bolts... Aftermarket good ones not the torque ones.. Will save your head gaskets and work much better...

I guess we will wait to see what everyone else says about running it or boring it. Part of me wants to make it an original 6.5l, the advantage is stronger psitons, but the disadvantage of over boring is weakening the block. I do long hauls sometimes 2500 miles, not much weight tho, aluminum trailer about 2000lbs and a 3000lbs car on it. 6.2l pistons melting on a haul like that for me would definately not be good.

My last haul was a 1500 chevy diesel 6.5l ext cab 4x4 on a aluminum trailer from New york to North Dakota. ALLOT of miles. And I was hauling with my 2001 chevy 1500 ext cab 4x4 V8, had some heat build up, when i was going up hills but I always stopped and let it cool off. It did a good job otherwise, have a big transmission cooler on it, and a big oil cooler.

Have to get this turbo diesel on the road soon, lots of work already palnned for it LOL.

This may be a dumb suggestion but...what the heck.

Have you guys thought about looking for forged pistons for the 6.2? If there is such a thing, you could get them instead of the bore job, run a little more boost without worry, and still have the stronger block.

Just a thought. I don't even know if forged pistons exist for a 6.2.

This may be a dumb suggestion but...what the heck.

Have you guys thought about looking for forged pistons for the 6.2? If there is such a thing, you could get them instead of the bore job, run a little more boost without worry, and still have the stronger block.

Just a thought. I don't even know if forged pistons exist for a 6.2.

Haven't seen any forged pistons for the 6.2, if there was they would probably be well over $1000. I have read that allot of peope put the gm-8 on the 6.2l and it runs fine. I am planning on running stock boost, with an intercooler, All of my cooling is all 1998 6.5l diesel stuff with high output water pump. I think it should run fine, stock boost is around 7 pounds on the gm-8?

This may be a dumb suggestion but...what the heck.

Have you guys thought about looking for forged pistons for the 6.2? If there is such a thing, you could get them instead of the bore job, run a little more boost without worry, and still have the stronger block.

Just a thought. I don't even know if forged pistons exist for a 6.2.

Thats what I've been thinking on also, a low compression 6.2.

You can make up most of the cubes with your displacement adder(turbo), have a stronger block, better head sealing and maybe a touch better economy with the less cubes.

Wonder if Wiseco or JE would make some, they will make about anything you want for a gasser for around 700 bucks.

Looked alot of places and no forged ones.. How about ceramic coating for the 6.2's?

Looked alot of places and no forged ones.. How about ceramic coating for the 6.2's?

The pistons should be strong enough, im just gonna run the 6.2L with a turbo, motor has only 100,000 miles on it, really clean, no leaks, should do the job, just add an intercooler to keep those engine temps down, you should be fine. Huntingfisher you should just run the 6.2l since it only has 300 miles on it, everything is pretty much brand new, you should get allot of service out of it on stock boost levels. I have read that the 6.2l pistons melt down or break when people are pushing 12lbs+ of boost, I dont think the 6.5L would last long either at high boost levels, probably would crack or detonate itself. Also when people install turbo kits they seem to become throtle happy, thinking their gas pedal is an on off switch, thus another reason for blown up motors.

I had a 98 grand cherokee 5.2L 4x4, I did allot of towing with it, sometimes towing other suv's on a flat deck for distances upto 2000 miles, and the truck ran fine till 200,000 miles, Long hauls like that generated allot of heat, but a good engine oil protected that motor for a long time. a diesel should be allot stronger. Just change your oil, maintain it well, and keep the temps down.

If you do bore it to a 6.5l you will probably weaken that block really good, and then be worried about it cracking on you.

We should make a group buy offer to JE sometime to see if they can make us some forged 6.2l psitons. it would end up being allot cheaper if allot of people went in on it. If you had the forged 6.2l low compression pistons you would have yourself a pretty strong motor, allot stronger and more durable than the 6.5l at a fraction of the cost of a good 6.5l block.

Just drop that 6.2l into your truck so you have your truck back in service, and then find another 6.2l to build up. The 6.2l's are pretty common, and you can buy a complete motor for 1/4 the cost of a used 6.5l.

Did you decide yet to bore or keep it the 6.2. I got my motor today the 6.2. Complete motor with under 300 miles... Yahoo..... I'm thinking of just throwing it in there and go. But would like the low compression or the better pistions since i have it out. Let me know what your doing and compare notes.

Did you decide yet to bore or keep it the 6.2. I got my motor today the 6.2. Complete motor with under 300 miles... Yahoo..... I'm thinking of just throwing it in there and go. But would like the low compression or the better pistions since i have it out. Let me know what your doing and compare notes.

Hello,

Great to see you got that motor. Im going to run it 6.2l with turbo. There are allot of guys running 6.2l turbo with the old motor set-up, the old water pump and single thermostat crossover. The problem is heat, so get a HO water pump an a dual thermostat crossover, and run it as a 6.2l think of maybe putting an intercooler in, it would drop the engine temps down greatly. Your motor has really low milage, run it as is. Unless your planning on running over 200hp at the crank, jst run it as is. If you bore it, you might weaken it, and once you torque down the mains, you might get cracks in the future. If you run it as is with some 6.5l cooling upgrades you should get a long service life out of it.

Your gonna have to strip that motor down to the bare block and heads, put your front timing cover from the 6.5l, so you get the crank shaft position sensor, then you have to put your electronic ip pump in, if the motor is pre-92' then you will have to run the 6.5l heads or the 6.5l injectors so that the turbo clears. You should put all your sensors on the 6.2l block from the 6.5l. Check your flex plate to see if its the same, if not run the 6.5l one. You will also need your 6.5l intake manifold, and the accesory brackets from your 6.5l. You can get all of that done within a day, just need some motovation, and a few cases of beer lol. If your 6.2l is pre 92' you probably won't have the turbo oil ta on the front of the block, so you will have to get oil from somewhere. Allot of people get a remote oil filter kit, and tap the turbo oil line into it.

Thanks

I don't think 6.2L pistons are weaker per se than 6.5L turbo pistons. The difference is that the 6.5 turbo pistons have hard anodized crowns which enhanced durability. Still, plenty of folks have run the banks kit on the 6.2 with no problems, so I wouldn't worry about it.

someone mentioned that boring a 6.2 would weaken it...if it is the older 6.2, then boring it would weaken it as much as a stock 6.5 since the older 6.2 blocks and the 6.5 blocks are the same.

the 6.2 blocks that were bored out to 6.5 were 599 blocks. I suppose you could do any of them but that would be the best to bore out. i'd just leave it for now.I run 10lbs of boost on mine all the time, and it runs great. I just used the 6.5 injectors in my heads, but it makes it where you gotta take off the turbo manifold to get the injectors out. might wanna use the 6.5 heads and get the .010 over head gaskets to reduce compression a little. then again, may just wanna run what you got til it blows a gasket. for a oil line, I have 3/8 metal tube run from the back of the block to the turbo. been working great for a long time. just have to bolt it down tight so it doesnt' vibrate and crack.
good luck. :cool:

Ripped the motor apart today and took some pics of the 6.2l pistons vs the 6.5l turbo pistons. Someone had mentioned on here that the 6.2l pistons were thinner than the 6.5l, thats not true because the 6.2l pistons are quite abit thicker than the 6.5l and they are taller.

Here are some pics,

The piston on the left is the 6.2l piston from a 1992 599 block piston on the right is a 1998 6.5l turbo diesel piston

http://img515.imageshack.us/img515/8321/dsc08056sl3.th.jpg (http://img515.imageshack.us/my.php?image=dsc08056sl3.jpg)

http://img525.imageshack.us/img525/5994/dsc08055pj9.th.jpg (http://img525.imageshack.us/my.php?image=dsc08055pj9.jpg)

Thanks

Prolly be best to compare by aligning the wristpins and the rod ends, rather than the piston rings

Final comparo would be to slice each thru the wristpin bores, then again across the piston 90deg to the bores