KZJ 78 tow capcity?? (1 Viewer)

Joined
May 24, 2020
Messages
22
Location
Vancouver Island
Hey I can't seem to find anything concrete on the towing capacity on these vehicles. I've seen some people say 2500kg and some say 3500kg (braked weight).

It's a 1994 KZJ 78 with a 1kzte so... obviously a bit older and coming up on 300k km's soon but what would a good safe bet be?

It would more than likely be pulling a single axle or double axle camper style trailer if possible.

Thanks guys!
 

GTSSportCoupe

2LTE abuser
Joined
Mar 23, 2012
Messages
7,282
Location
Victoria, BC, Canada
Hey I can't seem to find anything concrete on the towing capacity on these vehicles. I've seen some people say 2500kg and some say 3500kg (braked weight).

It's a 1994 KZJ 78 with a 1kzte so... obviously a bit older and coming up on 300k km's soon but what would a good safe bet be?

It would more than likely be pulling a single axle or double axle camper style trailer if possible.

Thanks guys!

Capacity and capability might be two different things.

I tow a 16' camper with mine. Single axle and loaded it's around 3500lb (unloaded 2500lb). It has electric brakes, and I setup a proper plug and brake controller for it. I installed a friction anti-sway device. I also installed a heavy duty custom rear hitch that connects to the frame. I added an auto trans cooler in-line (before) the factory rad one. (It's important to keep the original to help warm the ATF in winter.) I've also intercooled mine, tuned the engine up a lot, full gauges, 4 -core radiator, HDJ81 cooling fan, etc. And it's still marginal for towing....

From my experience, I would not recommend towing much more than 3500lb. This is engine aside. I just think there is too much compromise to stability and safety with any more than that. These vehicles are not made for towing. A pick-up truck would be a lot more ideal if you want a bigger trailer. Your KZJ78 could tow more, but it won't be comfortable at all, and you won't be able to do the speed of traffic safely. Maybe if you were in an area with sub 80km/h speed limits only.

Now I know the 1KZTE is a strong engine, but it's also an IDI turbo (they run HOT under load), and the light duty J70 series trucks have poor air flow to the front radiator. Heat will be a big issue driving into your prairie head winds, and especially if you hit the rocky mountains or anything further west. Getting your engine hot while towing may not end well for your cylinder head.... You'll need your cooling system in tip top shape.

To be honest, I think a small fiberglass trailer is best suited for these trucks (boler, trilllium, escape, that sort of thing).

IMG_20160605_110858954_zpslibwobnr.jpg
 
Joined
Oct 18, 2018
Messages
155
Location
Waikato New Zealand
I must admit the airflow thing has some truth, with a few 3000kg plus loads I've towed over a couple of hundred ks I have to carry ATF fluid with me because my wagon likes to boil the power steering fluid after a steep hill climb, funny this is the only thing that happens, oh and after a few long trips If I have to stop, getting going again is really hard work on the trans, you can feel the converter slipping its ass off and the heat just pumps out of it, so all in all no more than 2500kg I reckon unless your a butcher like me
I never suffer any real high temps on the radiator or the EGTs, before a steep hill I pull the wastegate pipe to get max boost (26psi) to help cool and I used the factory headlight washer jets to spray water on the radiator as a backup incase I start to see over 98 degrees - only have needed this once when I was towing and International 574 on a car trailer ( trailer weight 1100kg, tractor weight 2500kg)
 

GTSSportCoupe

2LTE abuser
Joined
Mar 23, 2012
Messages
7,282
Location
Victoria, BC, Canada
I must admit the airflow thing has some truth, with a few 3000kg plus loads I've towed over a couple of hundred ks I have to carry ATF fluid with me because my wagon likes to boil the power steering fluid after a steep hill climb, funny this is the only thing that happens, oh and after a few long trips If I have to stop, getting going again is really hard work on the trans, you can feel the converter slipping its ass off and the heat just pumps out of it, so all in all no more than 2500kg I reckon unless your a butcher like me
I never suffer any real high temps on the radiator or the EGTs, before a steep hill I pull the wastegate pipe to get max boost (26psi) to help cool and I used the factory headlight washer jets to spray water on the radiator as a backup incase I start to see over 98 degrees - only have needed this once when I was towing and International 574 on a car trailer ( trailer weight 1100kg, tractor weight 2500kg)

I love how you put that thing to work!

When you're towing those big loads, what sort of average highway speeds are you running? In Canada if you're going less than 110km/h you're dangerously holding up traffic on many of the main highways. Huge transport trucks get mad and pass when they get the chance. Wind turbulence can be downright scary when they pass.

Do you have brakes on your trailers?

I can hold 110km/h while towing my trailer, but temps will creep up on those hot summer days when I start to hit the inclines.

This year I may look at spacing my A/C condensor forward a bit more to let cool air in around it to the radiator. Removing the condenser entirely would be best, but then my family wouldn't want to go camping at all, haha.
 
Joined
Oct 18, 2018
Messages
155
Location
Waikato New Zealand
so by law here 90km/hr is the legal towing speed for cars and trucks, plus some of the roads are really hammered at the moment, however I can cruise along nicely at around 105km/hr towing, speed does not seem to affect temperature at all, I wouldnt want to push any faster than 105km/hr due to the cheap pads in my wagon, the big transport trailer is braked, but my smaller car trailer is not but I do have a kit for this to fit, Yep do not remove your AC, I don't think I would live past Christmas if I pulled my AC out!, Especially the wagon can be idling for easily 2hrs keeping a 9month old baby asleep
 
Joined
Oct 22, 2020
Messages
11
Location
Steilacoom, WA
Capacity and capability might be two different things.

I tow a 16' camper with mine. Single axle and loaded it's around 3500lb (unloaded 2500lb). It has electric brakes, and I setup a proper plug and brake controller for it. I installed a friction anti-sway device. I also installed a heavy duty custom rear hitch that connects to the frame. I added an auto trans cooler in-line (before) the factory rad one. (It's important to keep the original to help warm the ATF in winter.) I've also intercooled mine, tuned the engine up a lot, full gauges, 4 -core radiator, HDJ81 cooling fan, etc. And it's still marginal for towing....


Where did you source your trans cooler, intercooler, and radiator? I need to do all of that to mine.
 

Users who are viewing this thread

Top Bottom