Cummins NHC 250 versus Cummins 6CTA8.3

[farmer73]

I am looking at some M936 wreckers. Is it worth it to spend a few thousand more to get a M936A2 with a Cummins 6CTA8.3 504 cubic inches (8.3 L) turbocharged inline 6 cylinder diesel engine?

Would I notice a big difference on the highway?

Any reason(s) to avoid the NHC 250 in comparison?

Any reason(s) to choose the NHC 250 over the 6CTA8.3 on a M936?

Thanks!

 

[LCA078]

What do you want to do with it? You live in the mountains or sea-level flatlands?

If hobby use, then put the money towards the best wrecker you can afford as a hobby. Wreckers are dirty, nasty things that have a lot of issues compared to a regular truck. When you buy a wrecker, you're essentially buying a truck AND a hydraulic nightmare pushing 40 years of age. You're buying two headaches for the price of one. Unless someone has replaced all the hydraulic lines, replaced the cables, and babied the transfer case/main hydraulic pump, you could be in for a let down.

If you intend to make money with it or use it for it's true intended purpose (which is not hoisting flags on 4th of July), then the 8.3L is probably a better engine because it gets better mileage....but I still lean towards buying the truck in better overall condition.

If used primarily on the road as a commercial vehicle, 11.00R20 tires may not be a bad choice...but I'll defer to the experts here who have been there done that.

But to answer your questions, both engines put out about the same but there are differences that some owner who have owned both can comment on. Depends a lot on tires, weight, and altitude.

 

[Jbulach]

Been a long time since we had this question, everyone knows the 8.3 is better! I think all the 250 guys got their popcorn taken away and banned from the site.

Now on the serious side we kinda need to know how you plan on using the truck? Mostly highway, a lot of off road, mostly crane work, or are you going to try towing? The wreckers are heavy pigs to start with, in stock form the 250 is most likely better at slow speed or off road, 8.3 probably better for stationary crane work, just a slight edge in fuel economy, and neither are going to be happy towing another heavy truck on the hwy. @98G would probably be one to chime in on hwy as I think he has a decent amount of seat time behind both motors.

Edit:
LCA078 beat me on the keyboard and got me thinkin, an A2 on little duals might be nice on road!

 

[simp5782]

Better off getting an 816 wrecker. The wrecker unit is stronger overall with bypassing hydraulics when you pickup heavy things. Even things too heavy for the wrecker.

 

[farmer73]

Thanks guys!

I would mostly use it on my farm building structures, moving timber and boulders, and helping repair machines and trucks.

It would get driven on the highway a few times, and occasionally, if needed, to recover a truck or machine to bring back home to repair, but I also have an M920 for that purpose.

There is an M816 somewhat close I am also looking at. The best of the M936's I have seen is in very nice shape and has the smaller wheels and new goodyear rubber. The M936A2's I am looking at are both VERY clean and appear to have all the original gear and accessories along with allegedly very low hours and miles. I have been leaning towards the M936 or the M816 so far, but I wanted to be sure that passing up on the M936A2's was not a mistake.

I have looked at a handful wreckers that I want nothing to do with and have been looking for a couple years to find the right one to keep forever.

 

[farmer73]

Mostly flatlands and some rolling hills where it would be used on road. Off-road, terrain will vary quite a bit

 

[farmer73]

Better off getting an 816 wrecker. The wrecker unit is stronger overall with bypassing hydraulics when you pickup heavy things. Even things too heavy for the wrecker.

Hey Wes, thanks for that M816 info!

 

[simp5782]

@South has a few 936A0s he might part with in East TN.

Hey Wes, thanks for that M816 info!

 

[LCA078]

If

It would get driven on the highway a few times, and occasionally, if needed, to recover a truck or machine to bring back home to repair, but I also have an M920 for that purpose.

Nice on the M920. I think that's the Cummins Big Cam tied to a Cat 16 speed tranny, right? If so, lower your power expectations quite a bit with either the NHC250 or 8.3L Cummins. But since you have experience with MVs and know what you're looking for, I say you'll do alright regardless. My only advice specific for buying an M936 is to verify the transfer case, transfer case PTO, main hydraulic pump, and hydraulics all check out okay. If you have a noisy system when the PTO is engaged, try to find out where the noise is coming from before you pull the trigger to get an idea what you may be in for with a 'forever' truck.

 

[farmer73]

If


Nice on the M920. I think that's the Cummins Big Cam tied to a Cat 16 speed tranny, right? If so, lower your power expectations quite a bit with either the NHC250 or 8.3L Cummins. But since you have experience with MVs and know what you're looking for, I say you'll do alright regardless. My only advice specific for buying an M936 is to verify the transfer case, transfer PTO, main hydraulic pump, and hydraulics all check out okay. If you have a noisy system when the PTO is engaged, try to find out where the noise is coming from before you pull the trigger to get an idea what you may be in for with a 'forever' truck.

Thanks! I have definitely passed up on some that appeared to be in rough shape.

 

[farmer73]

If


Nice on the M920. I think that's the Cummins Big Cam tied to a Cat 16 speed tranny, right? If so, lower your power expectations quite a bit with either the NHC250 or 8.3L Cummins. But since you have experience with MVs and know what you're looking for, I say you'll do alright regardless. My only advice specific for buying an M936 is to verify the transfer case, transfer PTO, main hydraulic pump, and hydraulics all check out okay. If you have a noisy system when the PTO is engaged, try to find out where the noise is coming from before you pull the trigger to get an idea what you may be in for with a 'forever' truck.

yes, the M920 has a Cummins Big Cam tied to a Cat 16 speed. I also have a 1970 XM818 with the NHC250, so I know what to expect from that motor and 5-speed tranny. It seems like, based on what Wes said, a solid M816 might be good for me since I tend to push the limits on the hydraulics and have a big old Fiat Allis 220 that might need some repairs in the future.

I know that big hills with that NHC250 and that manual transmission will not be conquered at speed. I am still wondering if the Allison paired with the NHC250 is any different on the highway when you hit hills and if the 8.3 turbo makes a noticeable difference. It doesn't really matter, mostly just curious on this.

 

[98G]

I've had bunches of trucks of each type.

8.3 gets better fuel mileage. My almost 40k wrecker with the 8.3 gets substantially better fuel efficiency than my 23k M925 with NH250.

8.3 holds speed better when already at hwy speed and hitting a hill.

Loaded heavy and slow, off road? NH250.

Taking off from a stop, with a load? NH250. The 8.3 takes forever to build power.

I second Wes's comment about the M816. The 816 can be used at low rpm. The M936s require a minimum rpm to lube the transmission.

For a wrecker, dual 11.00s are better than singles. (Mine's on singles obviously)

The NH250 just sounds better and feels better.

8.3s bring a substantial premium.

I'd select based on overall condition of the truck personally.

 

[LCA078]

Nice collection and a beautiful background. Looking at 98G's wrecker makes think of something I've noticed a lot lately. And that's a lot of wreckers I've seen for sale don't have the vise on the front anymore. I'm guessing the vises are being taken off and sold separately or kept as a useful item. The vises were Wilton, right? Either way, I remember someone on the forum here said "I bought a vise at an auction and it came with a truck." Always makes me chuckle thinking that's how I'll explain it to my wife when a wrecker unexpectedly shows up at our house one day...

And all good points on advantages/disadvantages of engines and generations. Great info the older 816 can be used at low rpm. I bet that saved a lot of wear/tear on those systems compared to 936's engine and tranny having to be wound up just to spool out cable.

 

[farmer73]

I've had bunches of trucks of each type.

8.3 gets better fuel mileage. My almost 40k wrecker with the 8.3 gets substantially better fuel efficiency than my 23k M925 with NH250.

8.3 holds speed better when already at hwy speed and hitting a hill.

Loaded heavy and slow, off road? NH250.

Taking off from a stop, with a load? NH250. The 8.3 takes forever to build power.

I second Wes's comment about the M816. The 816 can be used at low rpm. The M936s require a minimum rpm to lube the transmission.

For a wrecker, dual 11.00s are better than singles. (Mine's on singles obviously)

The NH250 just sounds better and feels better.

8.3s bring a substantial premium.

I'd select based on overall condition of the truck personally.

Thank you!