6.5 high performance diesel engine swap

[M1008driver]

Even though my truck runs fine everyone says I will blow the engine if I keep driving at 65 mph. I am going to find out.

So would you put a new 6.5 high performance diesel engine in a M1008? The engine cost would be about $5000.

I am talking about the drop in model that is suppose to be an exact fit. I don't think I will be getting the turbo because it will just get me to the limits of my truck faster meaning 3 speed trans and 4.56 gears which I do not plan to change.

My Dad hit me in the head with enough wrenches growing up I think I could do this in a garage I have access to.

I plan on keeping the 24 starter and everything else about the CUCV, just swap the engine (WHEN MINE BLOWS UP).

So would you if you could afford it? See anything wrong with this plan other than the cost? My wife is paying...

 

[Chief_919]

A 6.5 without a turbo is going to make a few more HP than your 6.2, that is all.

 

[ODdave]

If I hit my d*** with a hammer I know it will hurt, Should I try it?

 

[M1008driver]

A 6.5 without a turbo is going to make a few more HP than your 6.2, that is all.

Yes, but I will have the better block and heads...

If I hit my d*** with a hammer I know it will hurt, Should I try it?

You would not believe the hours my Dad made me stand there and watch, learn, help whatever. He never went to the shop. So in honor of him I should do something with what he taught me in my life.

 

[Chief_919]

Yes, but I will have the better block and heads...

Not $5000 worth of better. And I have owned one.

You can get a GET block and heads from a GL 6.5 and build one for a fraction of that.

 

[southdave]

Cheaper I think to re-gear and put in an overdrive
example
new gears 373 installed front and rear around 1000 buck
gear vendor od about 2300
drive shaft re work about 200 bucks

 

[ODdave]

Yes, but I will have the better block and heads...



You would not believe the hours my Dad made me stand there and watch, learn, help whatever. He never went to the shop. So in honor of him I should do something with what he taught me in my life.

Then do an effective upgrade. Over-reving any engine is not good for it. I dont care if its a HI-PO engine, it will decrease the life and efficency of it. Leave your 6.2 (there not that bad) and get the R's down.

 

[M1008driver]

You can get a GET block and heads from a GL 6.5 and build one for a fraction of that.

I am trying to get away from this and do the work only once with a stronger block and heads. I would be making the swap the first time I threw a rod or blew a head gasket or whatever causes a overhaul.

common failures and defects of the original General Motors 6.5 diesel engine such as cracked block, broken crank, cracks in the main webbing, cracked cylinder heads, coolant in the oil, loss of power, hard starting, low oil pressure and oil contamination.

EDIT- I think I could do a swap, but rebuilding would take allot of beer as there are many important facts I do not know.

gear vendor od about 2300

From what I've found that is a very conservative price. $3000 is more like it plus I would want a new drive shaft and keep the old one. U-joints too. Approaching the price of the engine swap.

 

[ODdave]

So..... I guess I am missing something. You want a HI-PO diesel right? But you want to go faster? Hi performance means more power correct? It dose not mean the engine is biult to spin faster. Yes they make kits for diesels that alow them to run past the govened speed but it dose not mean they will last as long. Ther is a very limited market for the 6.5 as no mater what you do to it, it is still a pre chamber engine equipt with a IP that was designed to delive fuel at a max rate = to 25 hp per cylinder. With out a forced induction your not gonna flow nearly enough air to suport the added fuel. All of this aside, it is still not ment to overspeed for extended amounts of time.

Do as you please but I shure hate to see you spend more $ that what the truck cost and still not have the outcome you desire......

 

[SPCWarning]

Just my $.02, seriously consider southdave's suggestion (post #6 above). For way less than you want to put in the engine swap, you could pay someone else to do all his suggestions, (or even just swap the gears), and save money, make your 6.2 last longer, and not have your CUCV on downtime for nearly as long. That way, you have a good safe hwy speed that won't over-rev your engine. Again, just my two cents.
Jimmy

 

[M1008driver]

Hi performance means more power correct? It dose not mean the engine is biult to spin faster.

I am not looking for power and speed. I am looking for a stronger better built engine and they call them performance engines, not my term.

One forum says you can run a 6.2 at higher rpms all day long and if it is in good mechanical shape nothing will happen. Then this forum says don't go over 55 or you destroy your engine, thus the need for plan B. Some say get a Banks Sidewinder. Others say it causes premature engine wear. Others say just get a Gearvendor. They don't support the 6.2 anymore.

Anyway, I appreciate all the comments. I was just figuring some day when I need to do a rebuild I would do an engine swap.

EDIT- Gear Vendors NP 205 Transfer Case with Fixed Yoke, Automatic Transmission. $2,995.00

 

[SPCWarning]

True, you shouldn't run your truck over 55 mph, but that is with its original gear setup. They weren't designed to go fast. The problem with over-revving your truck is the 4.56 factory gears. Seriously, if you want to run at hiway speed without worrying about damaging an otherwise dependable engine, just have your gears changed to 3.73 or even 3.55 ratio. With 3.55 gears your RPM's would drop at hwy speed, you'll get better fuel mileage, and still have plenty of power for pulling. As far as the 6.2 being a strong engine, yes it is strong with the configuration in our CUCV's. Look at it like this. All our CUCV's were at some point in its life run like crazy in hills, on hwys, mud, sand, snow, etc by young Military personnel who "tried" to blow them up. They are set up to take that kind of abuse (at least when they were new). But look around...... there's a LOT of them left that still run perfectly with 6.2's. My 1009 has 73,300 miles on it. I have no idea who drove it and put 72,000 of those miles on it, but it wasn't hurt. Raising your gear ratio will help, and be a lot cheaper than Plan A. And that's just in the differentials, not adding a G.V. Having it done/setup by a professional will cost about 1/4 of what you're willing to put into another engine (which by the way, will also scream at 55mph with 4.56 gears). Just something to consider. Hope it helps.
Jimmy

 

[Miah]

I'm a bit slow in the mornings...but you want to replace an engine that you're winding hard & expect to blow at some point w/ a near identical engine that you'll be winding hard?

AFAIK there isn't any real improvement to a later non-turbo 6.5, I thought folk here said they were more prone to block/crank flex/crack issues & the older casting 6.2 block was better.

Would think the simplest way around issue would be to spend that $$ on a pro built 700r4 or other OD trans to get the rpm down for highway speed. you could throw the TH400 in the garage incase you felt the need to swap back at some point.

 

[reloader64]

If you like the truck and plan to keep it a long time, I say go for it. But I also agree that if you drive it hard enough, you will tear up the new one. Get the new engine, put in a 700R4, and drive it like it was a civvy truck.

Scott

 

[Sharecropper]

Another option to get faster speeds would to be to install TALL tires. My M1028 rolls along at 1900 rpm @50 mph with surprising power.

 

[jj]

I don't know about 3.55 gears for that 14 bolt in the back. As far as i know, the only available gears for that axle are 3.73, 4.10, 4.56, and 4.88. I have a G type one ton van with a 6.5 turbo and a 3.73 axle and a 4l80e transmission. This van will run all day and night at 75mph without even breathing hard. Ask me how i know. The Gearvendor is an expensive, intricate piece. I believe a 4l80e and a stand-alone computer to control it would be a far more durable and practical modification. And CHEAPER, too.

 

[dstang97]

Whats plan B when you destroy the 2nd motor doing 65mph?

 

[chevyCUCV]

I say drive it 65.
If you blow the engine and want to spend money on a new one, get a p400.
I dont think that you will have any problems, as long as your harmonic balancer is good.
I wouldnt do a gear swap as i think the 4.56's are a great feature.

 

[idM1028]

I don't know about 3.55 gears for that 14 bolt in the back. As far as i know, the only available gears for that axle are 3.73, 4.10, 4.56, and 4.88.

Superior Axle and Gear G105342OE - Superior Axle and Gear Ring and Pinion Sets - Overview - SummitRacing.com

 

[Tanner]

Superior Axle and Gear G105342OE - Superior Axle and Gear Ring and Pinion Sets - Overview - SummitRacing.com

...you presume that the OP has the ability to assemble a differential assembly, x2, and set the gear mesh properly.

'Tanner'