2-Stroke GM diesels.

[Chris142]

Well...My dream of being an owner operator have dwindled down to this.

A 1974 Peterbilt 359 and a set of bottom dump trailers

The truck belongs to a friend of my fathers. I have not seen it yet.

My 79 year old father who knows nothing about trucks did look at it yesterday.

The owner opened the hood. Told my dad that it was a V8, dad said it was green. Green V8 = 8v71/8v92. I know nothing about these other than they were called "Screamin Demons" and consumed large amounts of SAE40 oil.

How troublesome are these engines?

Dad climbed into the cab, not really knowing what he was looking at but did notice that it had 2 shifters.

Owner said it is a 5+4.
I've never driven anything like this before! Am I gonna die? Shouldn't this thing be in a museum?

All joking aside the price is right. I will look at it this week and try to figure out exactly what it is/has.

 

[Steve S]

The 8v92 should have a turbo on it. They are powerful motors when I was working out of the line drivers union hall I liked them .I Can't say whether they are good or not but I would buy a Cummins, Cats cost alot more than cummins or the Detroits [2 cycles]. The screaming came from the earlier 71 series with out the turbos due to the higher blower speeds . in the turbo models the blower was mainly to start them and for low rpm.

 

[Chris142]

Hey thanks for the reply Steve S. Unfortunatly this plan fell through also.

I will need $8,000 besides the cost of a truck just to get started. I can't see me getting 8K up unless I hit the lotto sometime soon

Also diesel fuel is up to $2.49 a gallon here! Guess I need to keep saving my $$ and hope that fuel goes down.

 

[Rev440]

Hmm, if the engine is green its prolly a 8v71 known affectionately as the 318 [318hp] If it had a turbo on it you'd be looking at the 350hp.

The first 92 models were red [o.t.r. vehicles]

2 sticks = 5 & 4
If you were to still buy the truck, Hopefully the auxilliary is an "open" pattern where you shift the stick in a "u" shape.
1st then pull back for 2nd, then up, over and down on the right for 3rd, then straight up for 4th.
Grab a gear in the main
then throw the auxilliary back in 2nd and grab 3, then 4.
Grab another gear in the main
then throw the auxilliary back in 2nd and grab 3, then 4.
...never throwing the auxilliary in 1st gear after the main is in any other gear than 1st.

Such fun holding the steering wheel with your left knee, while you reach over and grab two sticks to shift at the same time. LOL

 

[LarryL]

I had an MCI bus that I converted to a motor home and it had a Detroit Diesel 8v71. Great engine, easy to work on and made a lot of power, and ate a lot of fuel.

 

[LargeCarMan]

318 has just a blower and the 440 has blower and turbo. Two sticks are fun and really good for the dirt. You will need a Cal-T Puc permit, but I bet the hourly rate is about 75.00 an hour by now. Do what ever you can to get working in this business...you will love it. The broker takes 5% of the cut and if you lease the trailers...that's another 20%. Good Luck, LCM

 

[JHZR2]

wow, i didnt realize that these older trucks were 2-stroke engines... learn something every day.

JMH

 

[LargeCarMan]

They are like a Yamaha....got to keep them in the RPM range to run correctly. My mentor, years back told me to run the engines like you just slammed your finger in the door and were mad.

 

[JR]

Sounds like a 6-71 that I run for my part-time, no-time trucking company. It has a split fifteen speed. It took me almost 50 hours of gettin use to before I could grab all the gears without glinding. LargeCarMan is correct, these engine have all the power you will ever need put you have to run the engine like you just slammed your finger in the door and were mad. I also run a old AC dozer with a 2 stroke DD. Now that is a beautiful set of engines to hear screaming in your ear for 8, 10, 12, and sometimes 16 hours a day. All I can tell ya is I love the power and the sound of the engine under load and heavy use. If you get it to sound like a 300K honda with a pipe after the 16 year old pimple faced driver drops it in first at seventy and hit a altime high of 18 grand you got the screamin detroit at the right rpm range and are operating it correctly.

 

[rokky]

The two stroke jimmies are fairly hard on fuel. The 8v-92 turboed is a poor engine. The 8v-72 is a fine and proven engine. Not a lot of torque or horsepower but very tough. The 8v-72 could be turboed as well but still not much for power. Parts are cheap for these engines.

If you plan on doing a lot of heavy hauling, long distance you may want to rethink this purchase. Especially if there is a lot of adverse (uphill). You will be worn out from shifting gears and you will not make good time.

 

[Steve S]

From my experience the 8v92 engines had lots of power .When I worked out of the line drivers union hall I had the oppertunity to drive lots of different combinations ,the 8v92 feul squeezer would with an equal load "Thrifty Drugs company trucks" would blow away a 350 hp Cummins. I drove both of the mentioned trucks and I couldn't keep up with the 8v92 cause I was driving the Cummins.

 

[rokky]

You can squeeze out over 500 hp from an 8v92t but it will not live long. A company I used to work for got talked into buying one to replace a 12v71T in a huge truck. It would never make a year before needing an overhaul or other major work. They eventually had to scrap that engine and put the 12v back in.

The 8v92 was an attempt by Detroit to keep up to Cummins and Cat power of the day. The 60 series engines were still in developement.

Now the 60 series engines dominate much of the trucking and industrial scene around here. Mainly because they are so much cheaper.

 

[1040 WreckerMan]

We’ve run a lot of 2 stroke Detroit’s at work for a lot of years. The 6-71's were inlines engines and were gutless, but hard to hurt unless you lugged them. All the 2 stroke Detroits were blown, but due to the porting they are considered naturally aspirated. Without the blower one wouldn't run at all. The 53-71’s were usually green, the first 92’s were red and later silver (the Silver 92’s were electronic). The Series 60 went back to green.

The Series 71 was probably the best line Detroit ever made. They were easy to work on, reliable (in terms of the day) and made decent power. The most common of the 71's would have been the infamous "318". This was a 8v-71 NA 318 hp (at 2 ft/lbs of torque). If you didn't run the thing to the governor all day it would kill it in a hurry.

The Series 92 was originally adapted from a railroad design if memory serves. They were probably the worst of the two-stroke Detroit’s. We had about 300 of them in our fleet and have been the worst engine in the history of fleet (since the early 1940's).

The Series 60 is an excellent OTR engine. The 60 gets good mileage and has a good LTO. The 60 can't hold a candle to a big CAT in vocational work. However the CAT's get fairly poor mileage and are costly to repair, although they have an excellent service record in our fleet.

Although I'm looking to buy an a KW with a 71 in it for the nostalgia factor, I'm a CAT convert these days. Since we started buying the CATs I don't dislike being forced to drive nearly as much as I used too and we are not so far behind on maintenance as we used to be!

I miss the 2 strokes in a lot of ways, each one had it's own personality and ran and sound a little different than the next, something you don't really get with the electronic engines.

 

[huffmuds9320]

I know many of the older GMC New Look buses had 8V71 engines in them. They have a unique sound to them when shifting from 1st to 2nd gear. Electronic engines would be ones with the DDEC?

Anyone here know more about the 6V92TA? Did it come out after the 8V71 engines? There are still some city buses that still have the 6V92TA, doesn't have a lot of power going up hills. I'm guessing the tradeoff is fuel economy.

 

[XS650]

Quote:

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Anyone here know more about the 6V92TA? Did it come out after the 8V71 engines? There are still some city buses that still have the 6V92TA, doesn't have a lot of power going up hills. I'm guessing the tradeoff is fuel economy.

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There were many versions of the 6V92TA. I had some that were rated at 580 hp but usually dynoed at over 600 hp. They were for a special off road vehicle and wouldn't have lasted long in a truck. A marine version of that engine was rated at about about 630 hp. Also not a long life truck engine, but fun.

Unfortunately, what the others said about it being the end oif the road for DDC 2strokes is true.

 

[1040 WreckerMan]

Yes, the first electronic engine would have been the 92 Series DDEC, then DDEC II, III, IV, etc. The 92 Series was probably the least popular engine of the 2-Strokes. My personal favorite is the 71 Series as it had many improvements over the 53's, but they were still simple engines compared to the 92's. Public transit coaches usually never rated the 6V92's any higher than 350hp in a 60' coach. The current industry standard is 330hp in a 60' bus.

I ran some mechanical 8V92's that dyno'd at 550hp typically. They were in heavy spec on/off road trucks and they did pull pretty good. We were never able to get the same life out of them as the 71's that we were running before them.

XS650, funny you mention that Marine version. There was an outfit, I think in Oregon, that was selling new 92's to guys for re powers with more horsepower. The outfit was selling engines with marine fuel systems to bump the HP up. Somewhere I have a warranty bulletin from DD stating that any engine with Marine parts on a truck engine would be denied all warranty claims.

I do mis those old DD engines, they are almost ancient history on this coast.

 

[Steve S]

I went on a military base tour with my sons boy scout troop in May this year to the Coast Guard base in Humbolt bay we got to go out on some of the boats for rides I went out in a surf rescue boat she was 41 feet and very new the engines "twin" were electronic 6v/92 series !!! rated at 430 hp.

 

[brian fix]

I ran a large backhoe years ago ,Warner&Swasey Hopto 900 that had a GM 8V-53,yes its spelled correct,was a rare engine,that hoe had alot of power with a rock bucket tearing up a ten inch road (concrete),though its slow compaired to new stuff,compaired to some import machines it had great power,we also had a Koehring 1066 with a 8v-71 that was incredable for power,these made the Japan machines of the era look bad,at least20 years ago.BL

 

[XS650]

Quote:

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I ran a large backhoe years ago ,Warner&Swasey Hopto 900 that had a GM 8V-53,yes its spelled correct,was a rare engine,

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8V-53 was the engine used in the LVTP7 USMC Amphibious Assult Vehicle. 400hp at 2800 rpm. They sounded real purty.

 

[1040 WreckerMan]

The military is still buying many engines that are out of production for the rest of us. The Military can still buy Cummins 903's, 855's, KTA's, DD 71/92, etc. It's too bad that all of those engines are not available special order anymore. I suppose you could order an engine piece by piece from the parts counter, boy that would be an expensive engine.

I saw a 79 F-250 4x4 with a 6V53 and a Ranger 7 speed in it. The conversion was done very nicely, it was a neat truck but I imagine a bit on loud side in the cab!