Will My 6.2 Do It?

[painthorsman]

I just swapped out the 454 in my 1979 Chevy 4x4 Crew Cab Dually (K30) for a 6.2 diesel that I just totally rebuilt. The truck has it's original straight 4 speed (SM465) transmission, NP205 cast iron all gear drive transfer case, Dana 70 HD rear end and Dana 60 front axle (manual lockouts) with 4.56 gears. I havent done it yet but, I'm wondering if it has the guts to pull the 1998, 33 foot Dutchmen Classic 5th wheel trailer, with super slideout, that I have? The old 454 pulled it like it wasnt there but.. it also only got about 5.5 to 6 miles per gallon doing it! and about 8.5 to 9 mpg running empty. So far the 6.2 only has about 600 miles on it and it gets nearly 14 mpg! FANTASTIC!!! Comparitivly Speaking! Of course... top speed with my gear ratio is only about 75 mph!sound like it's wound tighter than a watch spring at that speed and I only tried it once, as it was bumping the gov. limiter pretty hard.

[urcndust]

I own a 83 with a Banks turbocharged 6.2 and I personally think you are asking a lot from it. My truck has a 4:10 rear end with an NV 4500 5 speed transmission. I've regularly pulled my 24.5' Coachman with a 17' fishing boat behind it for an estimated weight of 10,000# and I'm here to tell you, you better not be in a hurry. Max speed about 65 MPH on flat ground and head winds are your enemy. Any hills, she slows right down, however, I do pull in OD. I just figured that I'm on vacation and I'll get there when I get there. redface.gif I usually averaged 10 MPG. Good luck. Having said all that, your 4:56 gears are going to help you quite a bit. You might want to look into an OD unit at a later date.
Since the Duramax arrived, we cruise at 70 MPH, and the old 83 is semi retired.

[painthorsman]

I think the weight plate on the 33' Dutchman Classic shows a GVW of something like 8500 lbs. Unfortunatly I haven't had the money of late to spring for a turbocharger and a GearVendor Overdrive yet. Gear Vendors makes the only overdrive that will bolt up to the NP205 transfer case, as it bolts on the rear of the T/Case. You only have to shorten the rear driveshaft. There are other brands but... they go in between the transfer case and the transmission and require that you not only shorten the rear d/shaft but you also have to lengthen the front one. They wont work with the NP205 because of the shifter linkage/shift rails for the NP205 are located in the front side of it.
By the time I spend the dough to turbo and OD it, I will have way more in the truck than I could ever get out of it, even though it is an Arizona truck (very little rust) and late 70's 4x4 CC Duallys are rare in any condition! (only offered in 78 & 79) and most went to the scrapyard a long time ago!

[mhagie]

scott K, Don't sweat the money as to what truck is worth it's what you want that counts.
I have a truck that started life as 75 4X4, the only part left original is the frame, I have enough money in the thing to buy a real nice newer truck but I like the 80's style and besides I love doing the work.
If I had the bucks right now I'd put a d/max in one just to do it.
As you can see from sig my truck is a Johnny Cash special. :D

[arveetek]

Your truck will tow that trailer, but you probably won't be happy with it. That 454 was a lot more powerful than your n/a 6.2L, but, that doesn't mean you should give up.

I have towed my 29' Alpenlite fifth-wheel a great many miles, including a big trip from Missouri, to South Carolina, to Florida, and back home. The GVWR on my trailer is 8500 lbs (no slide). I have never weighed it, but I suspect that it weighs close to that. I have 4.10 gears with 28" tires behind my n/a 6.2L. It does a fine job, gets up to speed kind of slowly, but it will get wherever you want to go.

I am sure that your 33' with slide will weigh in closer to 9000 lbs.

One thing I have found is that the harder my 6.2L is worked, the better it pulls. It feels kind of gutless for the first 10 or 20 miles, but then the EGT's come down, and the power goes up. I suspect it has to do with working the injectors and cleaning them out.

I can't wait to see how my truck pulls with the turbo installed!

I average 13mpg towing my fifth-wheel. 18-19 unloaded.

I'd say just get out there and give it a try and see how it does. Don't compare it to the 454 you had, but think about how a 350 might be doing in the same situation!

Casey

[Heartbeat Hauler]

You might wanna just nurse it along unitl a good deal comes up on a clapped out truck that has a 6.5 w/4l80e. Sounds like you have good mechanical skills, just buy the whole truck, rebuild the motor and tranny and stick it in your '79 4x4, and " VIOLA " you got yourself a real nice classic truck that can tow w/ overdrive. Then install your 6.2 in the other truck and sell it for what you bought it for. You're not out any real money just time & effort. My $.02 worth.
JP

[Trip]

We recently sold our 86 3/4T with a 6.2J, 400 trans, and a 410 rear end. I thought the truck had decent power until we towed our 24' TT. We were extremely disapointed. Could barely get out of our own way, and any decent grade was pulled at 30 to 35 MPH. We've had 6.2s in the family for many years, so the truck was hard to sell, but our new Dmax/Allison is a real treat to drive and tow anywhere! :D