thefallman

btw thats the diesel out of the npr 1.5 ton commercial cab over truck 97 or newer.

AH64ID

That was my thought... Its a 5.9 I6 minus 2 cyls, so a 3.9 I4.. and still weighs in at 1K lbs... your frame would not be happy... it would take some serious reinforcement to handle the weight and tq, but very doable and would be SWEET....

offroad4x4yota

The toyota frame rails are pretty stout being that they are boxed in but it would require some extra cross members. I just want to be able to tow heavy loads with it. The suspension will be getting totally redone with coilovers up front and stout leafs in the rear with dana 60's front and rear. I just thought it would be awesome to be able to use my 89 as a tow rig rather than buying a new truck like an f-250, HD, ram 2500, or and Tundra which all cost an arm and a leg. When I can put a new engine, transmission, t-case, axles, and suspension and still save a ton of money and have alot cooler truck.

AH64ID

Stout for a mini yes, handle the tq of a big diesel when towing, probably not... beides thats too small of a rig, size wise, to safely tow big loads even with the power and braking ability.. just not something I would turn into a tow beast...

Pickup a 91-93 cummins, plenty of power, cheap, and reliable as hell...

offroad4x4yota

I think i will go with the 4bt. It has plenty of power gets about the same if not more fuel mileage than i get now and has a ton of power. Are there any other swaps that might be cheaper, easier, and get a better return on power and fuel mileage?

curtiswyant

How 'bout a SBC 350? You'll have tons of leftover money (for beer) and time (for drinking)!

thefallman

oh to say nothing of DOT and the fact that your truck is only licensed to tow so much and definately cant belicensed to tow F250 Loads. BTW think about stoping power without the wieght of an F250 even if you have the Dana 60s you still wont be able to stop quickly with heavy trailer. it will just shove you around.

elripster

I was going to bring up the towing issue. Typically braking potential is what limits your tow capacity, not the engine. That means you need big brakes AND a heavy vehicle to have enough traction at the wheels.

If you wanna tow, get a long wheel base full size, a mini will get owned by a heavy trailer real quick. (wait 'till the wind blows...) An overly large diesel will just get your and your truck into a situation your chassis and brakes can't get you out of.

Frank

offroad4x4yota

I do see your point, but wont the add weight of the diesel and dana 60's make up most of the needed weight. and I also realize that the brakes would have to be upgraded and trailer breaks would be an absolute. The only thing I would really ever tow is my rig which will be fairly light.

offroad4x4yota

How much hp and tq does the isuzu and the toyota diesel produce? would they make enough power to tow without any power issues?

AH64ID

Its still not enough to make it a 3/4 ton tow rig... period... even with 1 ton brakes on the 60's... the truck isnt designed for it, and cant handle it... Look at the GVWR, its less than a 3/4 diesel weighs empty....

And the $$ you would spend would be more than picking up an older 3/4 diesel.

If you want to tow w/out power issues, then you need a 3/4 or 1 ton...

thefallman

the isuzu that im thinking of has somewhere around 190hp and like 425 lbs./ft cant find the engine designation??

heres the current specs for the current engine
Engine
-Type Turbo/Intercooled Diesel 4HK1-TC
-Displacement 5.2 L (317 CID)
-Horsepower (Gross) 205 HP @ 2,400 RPM
-Torque (Gross) 441 lbs./ft. @ 1,850 RPM
-Oil Level Indicator Dash-mounted oil level check switch and light
Engine wieghs 1036lbs


and the industrial version is the same hp but has 521lbs./ft and the Marine version has 550lbs./ft
also the one i was talking about originally is an older version of this same engine i believe.

AH64ID

Still a silly heavy motor for a mini....

even thou the frame is fully boxed you would still destroy it with a tqy diesel...

thefallman

heavy yeah but with some reinforcement that would make one heck of a crawler

i can really sympathize with offroad4x4yota when i originally was thinking about a swap this is the one i was going to do. I mean behing able to tow 12000+lbs at 70 plus down the highway would be SWEET i mean think about a Toyota pulling a CAT Skid Steer. Actually the bigger problem would be the hitch anything that has more then 500lbs tongue wieght is going to rip the frame in the back of your truck. i speak from experiance. since the fram isnt boxed at the hitch mount it tears and will drop your reciever on the ground.

chopitrakeit

I am doing it now. I have my Cummins 4B, 3.9 L. Adapter for chev 700R4 tranny, NP205 case. Major decision is whether it goes in the 89 4R or the 95 PU. Will be into it this winter.

AH64ID

It would be SWEET swap, dont get me wrong.. I considered it many a time, years ago.... But it is not something I would do to tow with.. you just cant tow 12K lbs with a toyota.. and not because of hp.. there are MANY reasons.. Now hwy cruising, and crawling would be SWEET....but not a dedicated tow rig..

FredTJ

Actually I think it wouldn't be a good crawler at all.
The weight bias would absolutely suck..

We wheel (rock crawl) in the big stuff out here in S. AZ. and weight bias (along with total weight) is a huge factor in performance.




Fred

thefallman

true true

and yes unfortunately as sweet as it would be to use it as a dedicated tow rig there just isnt enoug braking power there

AH64ID

Its not so much the brakes that bug me, as you can easily (considering the rest of the work) keep 1 ton brakes on the 60's (as they are 1 ton axles).. its the sheer size of the truck, or lack there of....

elripster

I think an excessively heavy torquey engine, heavy axles, etc... will start a lot of engineering tail chasing. You strengthen one part only to break the next one down stream and so on.

Also, for towing, it's more than just mass. The vehicle's wheel base is very important. For example, I towed a 5000lb 25 foot trailer from San Diego to Austin Texas with a GMC extra cab full size. When the wind blew, the tail wagged the dog but was controllable. It stopped Ok, but not great. It got up the hills good enough but struggled. This is with a long wheelbase V8 powered vehicle. Just the lack of wheel base will make towing with a mini very dangerous. You have to worry about ripping suspension from the frame, etc...

Trust me when I say, the truck was engineered for a certain tow rating and exceeding that is wicked unsafe. If you want to crawl, the gearing advantage means even very small 2.4L 4 cylinder engines are fine. The larger heavier engine will just break more stuff and bigger engines are really for on-road drive ability or sand.

What do you really want this truck to do for you?

Frank