Chevy Diesel Swaps 6.2 or 6.5 (1 Viewer)

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Wanted to get an opinion as to what Chevy diesel to drop $ on. Ive got a FJ62, and have Marks Adapters Chevy 350 adapter for my auto. Have heard that this adapter allows for a 6.2/6.5 to work as well. Any insight to these motors for this application?
I've had buddies with 6.2's have excellent results, but know that the 6.5 had some "issues". While a Cummins would be great there are a ton of the 6.2/5's out there for little investment, and are easily rebuildable.
I've currently got an OME 3" HD lift and planned to add 2" lift shackles for additional lift. If needed I could do a SOA (with removal of spring).
Any advice would be highly appreciated.
Thanks!
 
I think there were issues with the 6.5 with cracks in the block. Somewhere I read about the serial number to check to see if the engine you have is susceptible to those problems or not. I've heard of injection pump issues with the 6.2 or 6.5, not sure which.
 
I have a 6.2 in a 84 sub and a 6.5 in a 96 sub. Both of them are great motors. If you want to know which one is best for your aplication I would recomend calling Bill Heath at Heath Diesel. My 6.5 is electronically controlled and puts out gobs more power than my 6.2. All of the chevy diesel builders like to use the 6.2 block with the 6.5 heads. The 6.2 blocks are stronger. The only issues with the 6.5 is that some of the late model ones 98,99 and possibly 97 had some issues with some additional oil piston sprayers in the block. I dont know the exact details. Also similiar to the 3fe there were head cracking issues if the block was severly overheated ( I had this happen to my 6.2). Fortunately there are new aftermarket castings with improved designs readily available which are cheap (unlike the 3fe, ask me how I know) Since my 96 sub was totaled a few weeks ago and it has all of the external aftermarket ad ons i am going to pu it in my 55 which curently has a 350 in it. The only thing that is really wrong with both motors is that they do not come with intercoolers, which a much needed add on on these motors. Since you are going to be doing a lot of work it will definately be worth you time to add one in. When I do my conversion I plan on using my 4l80e auto in it. On my 84 sub I have a 700r4 which has a great overdrive, but the transmission is a little weak for heavy duty towing. No matter which transmission you use make sure to install a electric transmission fan cooler on the transmission. the diesels produce a lot of torque and heat. If you go with a 6.2 it will definately need a turbo. These motors are dogs without one. You should start taking a look at craigslist and see if you can pick up a complete running diesel 4x4 sub. I see them all of the time for around 1-2K. If you found a 3/4 ton it would have a turbo 400 transmission with 1 ton axles. Then it would be a simple matter to do a drivetraina and axle swap. You could probably sell all the toyota parts and alsmost break even.If you do go that route get a diesel compression tester from harbor freight. I prefer the electronically controlled diesels over the mechanical injection diesel, however I bet that both could put out the same amount of HP given the correct injection pumps. My 96 3/4 sub was a great tower it would regulary pull our maxed out 21' toy hauler which was at its load limit up some very steep grades. The one big issue with it was the lack of an intercooler.
 
6.2's usually have many problems.6.5's are better,Fords are MUCH better;) .
 
You can get by without any lift at all with the 6.2/6.5.

They fit well in a 60 except the steering shaft area. A spacer plate between the steering box and frame aleviates that problem.

A stud girdle for the main bearing caps is a good modification for the 6.5.

Turbos are great, and would like one myself...but be prepared to hack out areas of your inner fenderwells on both sides. A non turbo's 6.2/6.5 can use a stock radiator. With a turbo I think a larger radiator would be in order. A larger radiator means not being able to use your stock A/C evaporator and hoses due to where the outlets are and line holes are in the radiator support.

Although the injection pumps aren't spectacular on any of these engines, the 6.5's (94 up) electronics can be moved away from hot engine components to improve reliability.
 
I prefer the electronically controlled diesels over the mechanical injection diesel.

Yes, but an electronically controlled diesel is more of a PITA for a swap since you need all the computers. A mechanical injection needs the starter and an altenator connection along with glow plugs or glow screen and you're good to go.

Most any diesel is a dog without a turbo. Turbo's are the BEST power add you can give a diesel.

Of all the domestic diesels my choice would be a Cummins.
 
duramax ;)
 
If you are going to put any 6.5 in your truck be sure you get a very late model one with the block cast by International Harvester the IH will be cast in the valley between the heads this is the block that you want.
 
Honestly, I had'nt even thought of going with a turbo with this. Was just interested in a less expensive diesel conversion with a little more "scoot" power than the 62 currently has, better MPG, and can run on bioD.
Is my understanding correct that the 6.2/6.5 has the same mounting/flywheel as the 350?
Are there any particular years of the 6.2 that were better than others? What else should I know about before I really get into this?
Seriously, its much appreciated!
 
Yeah, a DMax!

With some minor tunning, you could easily run 600hp and about 1k of tourgue.

Now, that would interesting. A 12 sec LandCruiser!!
 
Besides the power of this motor......What kind of mpg will you get with this motor? Can this diesel run decently on some bio or WVO?
 
The naturally aspirated 6.2 won't feel any peppier or quicker than what you got now. Feels like driving a 2F. Turning up the fuel delivery in the inj pump helps power a little. The 1 MPG loss is worth the 5-10 HP power gain.
Stock pump I was getting 19MPG hwy and 17 MPG city.
Now get 18MPG hwy, 16 MPG city.
I have found the Inj pumps not very tolerant of error in my experience with WVO. But I'm sure they would be fine with biodiesel.

There are no years dramatically worse than others. The heads slightly weaker on earlier engines, the blocks slightly weaker on later engines as Crashly descrived above, but no problems of epidemic proportions. Picking the year isn't that great of deal, run what you got or easily find. The late eighties/early nineties engines are reputed to be slightly better. Late eighties/early 90's came the serpentine belt and assy setup which is nice. The most sought after is the 1993 because it was factory turbo pre-electonics.

Same bell housing pattern as the 350. Flywheel is different. The diesels flywheel is ext balance. The diesels bigger starter nose doesn't fit in all gasser bell housings. Best to use a diesel bell housing, or cast iron one from HD trucks from the 70's with the open bottom.
 
Also you'll probably want to consider an overdrive if drive on the highway. The diesel doesn't feel comfortable running higher RPM's. If I run over 2300 RPM's, the noise level increases and hwy MPG's drop dramatically down to like 12- 13 MPG.
 
good practices with diesels are to not overload the engine on a hill(chugging with foot to the floor) or your EGTs get too high and can cause cracks. A pyro gauge helps monitor that.

Also letting it warm up slightly before driving is smart. A min or two is enough for the heads to be warm enough for complete combustion with out bad timed detonation.

Letting the block warm up prior to driving or pushing it hard is good too.
 
Stock domestic Diesels are much more forgiving of lugging the motor.

If the motor is turned up, then you need to worry about EGT's.

Those Chevy diesels will give you more hill power but not much if any more pep..

overdrive will be a good thing.

You can also swap to 3.70 gearing if you are still running at a high RPM..

What size tires you planning on running?
 
J34 Westinghouse, still the most creative swap.:D
Although, kerosene is more expensive than diesel fuel.

Developed by Westinghouse Electric Corporation in the late 1940s, the J34 engine was an enlarged version of the earlier Westinghouse J30. The J34 produced at least 3,000 lbs. of thrust (depending on engine series) and was twice as powerful as its predecessor. Several different series J34s were used in US Air Force experimental aircraft during the 1948-1953 period. A J34-WE-22, rated at 3,000 lbs. thrust, powered the tiny McDonnell XF-85 "Goblin." The McDonnell XF-88A used two J34-WE-15 engines, each rated at 3,150 lbs. thrust, while the XF-88B used two XJ34-WE-19s, each rated at 3,250 lbs. thrust. Power for the Douglas X-3 "Stiletto" was provided by two XJ34-WE-17s of 3,370 lbs. thrust each. The -15, -17, and -19 engines were fitted with an afterburner for additional thrust when needed.

SPECIFICATIONS
Model: J34-WE-34
Compressor: 11-stage axial flow
Turbine: two-stage axial flow
Thrust: 3,500 lbs. (No afterburner)
Thrust: 5,000 lbs+. (With afterburner)
Weight: 1,200 lbs.
Max. RPM: 12,500
Cost: US $68,000
 
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Stock domestic Diesels are much more forgiving of lugging the motor.

If the motor is turned up, then you need to worry about EGT's.

Those Chevy diesels will give you more hill power but not much if any more pep..

overdrive will be a good thing.

You can also swap to 3.70 gearing if you are still running at a high RPM..

What size tires you planning on running?

stock is the key word.

if you run larger tires or different gears than original then you may alter it enough from stock.

I've never put a pyro on a domestic diesel to see how hot they get. Anyone?

I know the yota diesels get damm hot.
 
Chevy 6.2 with gale banks kit, noting modded, 900, between the head and turbo.

Cummins 6BT much built and modded, 1200-1300 between head and turbo.

The 6.2 wouldn't really climb above that even when used hard. Banks says that 1000 is what you want to keep it below with stock pistons. The 5.9 would climb higher if pushed hard on a long steep grade with a load, but that was where we backed off to prevent damage.


Mark..
 
Considering the overdrive...I had planned on just continuing on using the 440 tranny. Currently with 33's I dont get maybe 2200 on the highway.
Might step them up to 35's though "to control the gearing". I assume that someone on the board could back me up when I try to explain to the Mrs of this arguement.
Either there is still confusion with these motors or Im still missing something. Seems there are alot of guys who badmouth both the 6.2 and the 6.5, but cant give specifics or are confused with the early 350 "knock off" motors. Looks like there are a TON of hardcore rigs running both motors worldwide (just not here).
Yeah, I'd love a Cummins/Duramax/Powerstroke, but come on...if I were to go that way I'd go buy a truck and have to sell the 62! Figure that going with a 6.2 for the FJ62 would be an inexpensive diesel swap that quite a few guys would like to do if we could clear up the misconceptions of these motors.
A big thanks again for helping me sort all this out for me and the community!


BTW: Anybody got some pic's of the end result?
 

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