blackandgold51
1/2 ton status
Not that I would do it but just wondering 
CK5
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Is it possible to put a Cummins in half ton gas operated 1989 to 91 Suburban 4x4?
- Thread starter blackandgold51
- Start date
yes but the 1/2 ton and even 3/4 ton axles will be crying for help over the weight .
best to beef up few other areas also . but yes its done on our body styles with the cummins swapped in .
best to beef up few other areas also . but yes its done on our body styles with the cummins swapped in .
wetoolowdingbangow
1/2 ton status
Exactly. I think its also important to note that the frame probably wouldnt put up with that 1000lb torque monster. I wouldnt put a cummins in anything but a 1 ton frame and axles....just like they come off the assembly line.
Anything is possible...
blackandgold51
1/2 ton status
How about getting a 1 ton frame from a C or K 3500 and dropping the suburban body on the farm and putting in the Cummins?
Wheelbase is close (129" vs 131.5") but the shape is different so you'd have to use a body lift big enough to make it work plus rework all the body mounts behind the front floorboard.
If a guy can put one in a 70 monte carlo anything is possible...
beags86
Eastbound and Down
Link?
I've seen an Allison Aircraft V12 installed in a 70's Monte Carlo before!..
..dont know how "streetable" it was,but it fit...
..dont know how "streetable" it was,but it fit...lame too
Sure you can. I really don't even see the problem with the 10 bolt front axle either, if it's in tip top shape. K20's had 8 lug 10b's up front obviously and when they had a gooseneck trailer hooked to them weighing, say 10K, 30% of that weight is tongue weight on the truck, and 25% of that weight is added to the front end. That would add more weight to the truck then what a Cummins would add over a BBC.
As far as the frame, box and reinforce as much as possible, and watch the power. Leave it pretty close to stock and it would probably be fine.
As far as the frame, box and reinforce as much as possible, and watch the power. Leave it pretty close to stock and it would probably be fine.
That Monte Carlo is bad azzzz.
Possible? Yes. Easy or cheap? No.
But it would make for a neat project. I would suggest reading through Mosesburb's thread here to get some ideas. His Suburban is a '72, so a lot of the body fitting would be different, but he did a thorough job of documenting each and every little tweak that was required to make his 6BT fit. If you are comfortable with the number of little things that require adaptation, and the overall pricetag, go for it.
But don't jump into a project like this until you have a good understanding of how many things aren't compatible between these trucks and those engines.
blackandgold51
1/2 ton status
If gm was thinking at the time, they would've had Suburbans (and pickup trucks ) with installed Cummins.
Those vehicles would've been selling left and right.
What was gm thinking ?
Well, for one they were working with Detroit back in those days. 2, not counting before the mid 80's, Dodge and Cummins likely already had an agreement worked out by, likely about 1985. 3, GM probably wouldn't have sold them left and right, at least in the Suburbans. It's why there is no Dmax available in the burb, it drives up the price of the vehicle so hi that there probably wouldn't be enough sold to justify the option. It all made total sense for that 80's era, Dodge did right by beating everyone else to the B series because they needed it the most. Ford had it's reputation to ride on, on making good HD pickups, and Chevy's 454 also had a great rep. Dodge had jack. The B series put them back on the map again.
I'll add a few points: GM did have a 1982 diesel engine that they put in these rigs. Suburbans included. It was a nice engine, a very efficient workhorse. A good fit for 1/2-ton trucks, and a decent fit for tow rigs. Even being a good compromise engine, offered in all types of truck, it didn't sell all that well. Ford and Dodge diesel engines were limited to 3/4-ton and 1-ton workhorses, selling even fewer. Not many of the heavy diesel trucks ended up in the hands of residential customers. Suburbans were primarily marketed toward families with lots of people/stuff to haul. What soccer mom would want to pay for an expensive towing engine on vehicle primarily used to haul people? It just doesn't make sense, given the marketing of the vehicles at the time. Plus, the 350 Olds diesel had just shown that the non-towing market was not very enthusiastic about diesel technology.
Secondly, the Cummins-equipped Dodge rigs didn't come out until 1989. A full generation after the 6.2 engines. Squarebodied trucks were already out of production by the time that the 6BT entered the automotive world. That's a really big reason why there weren't any square-bodied Cummins trucks. The R/V series was only in production for a couple more years. So unless they had beat Dodge to market, the earliest they could have had a 6BT would have been in the GMT-400 era. Even the original 6BT (or was it 6B?) agricultural engine hadn't been developed when the 6.2 hit the market.
Thirdly, the original specs for the Dodge 6BT aren't much different from the 6.2 engines of its era (looks like it's just torque numbers):
Cummins: 160 horsepower (119 kW; 162 PS) and 400 pound-feet (542 N·m) (source)
6.2 (late): 160 hp (119 kW) @ 3,600 rpm / 285 lb·ft (386 N·m) @ 2,000 rpm (source)
6.5 (turbocharged): 215 hp (160 kW) @ 3,200 rpm / 440 lb·ft (597 N·m) @ 1,800 rpm (turbocharged) (source)
(I agree it's not the best source, I'm just trying to illustrate that the engines weren't developing 250+ HP when they came out).
The 6BT is a nice choice if you wanna build an engine, but in OEM form, in 1989, the specs weren't drastically different. So why would GM chuck out its R&D costs on the 6.2 and start paying another company for even more expensive engines? It did provide a much-needed kick in the pants to get going on a turbodiesel engine. And when the 6.5 came out (1992/1993), it's numbers look even nicer when making Cummins comparisons. GM's design did run out of design margin first. They could not crank up the power numbers as far as Dodge did later on, and they started running into reliability issues when they tried. But looking back to the original 1982 goal (good mileage in trucks that aren't super heavy), the 6.x series does a fine job.
So it's kinda like asking why 1972 Blazers weren't ever offered with fuel injection. It wasn't out yet, and the customers of that time probably would not have been willing to pay for it, given how well the existing engines were operating (by 1972 standards).
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I think that source is wrong. The 160 horse engine was 440 or so torque. The rotary engine was even less horsepower and torque. I wanna say 145 but don't quote me. I have a 190 p-pump and said to be almost 500 torque. Also not sure on the Detroit with 440 torque. They are the same engine between 1/2 and 1 ton, so that would mean the 1/2 tons and Blazers would haul serious ass!!!! Even a 1 ton would shit and git. Buddy has a 2000 1 ton dually that is an absolute turd. Truck by itself is OK, but hook a trailer to it and can't get out of it's own way. Its a 2wd, he is gonna cut the front output off a 241 just for the low range so he can use it. He has a tree cutting business and can get heavy at times. If you just have to have a diesel, I'd go Cummins. Sky is the limit of what you can do to it.
It might be. Here's another source that lists the same numbers for the early years. Wish I had Dodge dealer paperwork to get real numbers from.
I pulled up dremu's GM brochure page and found 145/285 to be the HP/torque numbers for a 1991 6.2 engine in a 1/2-ton (155/285 in a P30, other values in a range between the two). Not the same as the Cummins, but close for the heavy trucks and about 10% less for the light trucks (torque is a different matter).
My point wasn't that the 6.x series would keep up with a Cummins, but simply that they were close enough to make redeveloping the GM diesel line a bad business move in the early years. After a few more years, when Dodge cranked up the numbers, GM got left behind. But by that point they were no longer selling them as 1/2-ton commuters/mileage queens (and they should have developed a better towing engine then, rather than trying to turbocharge a slightly-tweaked 6.2).
FWIW, the engines aren't completely the same in 6.2-powered light, medium, and heavy duty trucks. Emissions equipment, at the very least, is different from configuration to configuration.
blackandgold51
1/2 ton status
The 454 is and was a good engine from gm.
The only thing for that engine was fuel mileage . it drunk gas like no tomorrow.
One time someone said to me to take out the 350 and put in a 454 and I said no way!
