HJ45 Towing Capacity?

[Joe45]

Hello!

Does anyone know what towing capacity would be for a 1980 HJ45?

I’m thinking of towing a travel trailer for now.
Thanks!

 

[Paddler Ed]

Australia (NSW) for that era runs on 1.5x Tare, so my 1978 HJ45 with a heavy steel tray gave me about 3,000kg tow capacity. It was happy with a ~750kg trailer on the back, I don;'t know if I'd want much more...

 

[cruisermatt]

most of them can barely drive themselves around.

 

[whitey45]

Travel trailer will tow the 45 faster!

 

[Living in the Past]

The FJ45 in the US was under 4,000 pounds. Can't think a HJ45 could be that much heavier. Even with a stronger engine and better brakes your still dealing with a weight issue. Well adjusted trailer brakes would be a must have. Even with trailer brakes your still dealing with a slug that's a hazard on the highway. Would not suggest installing a turbo on an H engine. With a heavy load you'll just speed up the killing the engine. Last thing I would want traveling is a blown engine far from home. I love my 40s but they are all just toys that are being towed not the vehicle towing. Logic wins out over being cool for me. I have a second gen Sequoia and fourth gen 4Runner with a V8 that doing the towing. The heaviest is a car hauler with an 40 series on it. That's only happens rarely. If I wanted to tow a travel trailer would buy a 3/4 or 1 ton diesel for the job.

 

[45Dougal]

Theoretically we'd be limited to about 1500kg based on weight of the truck alone.
My HJ will sing along happily on the highway at 60 - 65 but any steep hills will see me in second gear even without a trailer.

I recall you posting that your cruise speed was already a lot lower??

Maybe if you get it tuned up and stick with fairly level roads you could pull a light weight caravan or trailer tent?

I've run some injector cleaner through mine recently but I haven't delved yet into pulling them apart yet.. maybe in the winter

 

[-MaTTi-]

Does anyone know what towing capacity would be for a 1980 HJ45?

2000 kg with brakes, 825 kg without.

 

[MOTOV8R]

if by travel trailer you mean small pop-up tent camper, you should be golden.

 

[Joe45]

Thanks for the replies.
By "travel trailer" I mean something below 4,000lbs. Hopefully less.
Something like a Casita or an RPod.
For now it would be to live in temporarily; probably just tow it to the RV park. Maybe around country roads. No highways.
I don't like highways anyway, even in the more modern vehicles, and especially not while towing.

My top speed is like at 45MPH right now.

Plans for the HJ to improve this is to swap in a 5 Speed H55 and probably a 1HZ engine, power steering.

I may, however, be forced to live in the trailer for a bit and have the HJ as a daily driver for a bit. This sucks because I need to rewire it and also want to restore it.
But I have to do what I have to do.

The 40s are snails because of the transmission usually and sometimes the wimpy engines. Mine was a farm truck on a coffee plantation: a glorified tractor. But I am sure it can be made into a comfortable and capable vehicle both on and off road. I don't need to do 80mph, but I am sure I can get it to do 60-65 easily when finished.

And by "comfortable" I don't mean plush like a 2023 Land Rover Defender. I think good insulation and Recaro seats will make a massive difference.

 

[45Dougal]

I think something needs tweaking on yours.
My 1H can go a lot faster than 45 and I'm carrying already a lot more weight than you are with my roof, seats, kitchen etc.
How is your fuel economy?

 

[AussieHJCruza]

I've run a HJ47 at about 3k kg which as @Paddler Ed says would be theoretical legal limit here. Properly working trailer brakes are mandatory and you don't want to be in a hurry. H41 shorter first gear helps too

 

[Joe45]

I think something needs tweaking on yours.
My 1H can go a lot faster than 45 and I'm carrying already a lot more weight than you are with my roof, seats, kitchen etc.
How is your fuel economy?

I calculated about 22-24 mpg
I may have ridiculous gears like 5:56. Have to check. If so, I can always go down to 4:11, but a 5 speed is still needed

 

[45Dougal]

I calculated about 22-24 mpg
I may have ridiculous gears like 5:56. Have to check. If so, I can always go down to 4:11, but a 5 speed is still needed

Mileage sounds good, how's the engine speed at 45mph?

Is the max engine speed limiting you on level road or is it just limited by power?

 

[Joe45]

Mileage sounds good, how's the engine speed at 45mph?

Is the max engine speed limiting you on level road or is it just limited by power?

I'm on level road most of the time. In Boone/Banner Elk, NC I cut through Valle Crucis and there were some really steep hills. I had to use 2nd gear.
Engine RPMs seem fine up until I get to about 45MPH, then it's kind of like I hit a wall. Same feeling as when you're in low gear and accelerate: the engine revs up, but it dosn't go much faster.

Not sure what good it'll do, but here is a video that shows me doing 40MPH at one point, and also a little faster.

 

[45Dougal]

Hard to tell in the video but the engine rpm sounds a lot lower than mine at 60mph.

Could be that someone messed with the governor settings and reduced the max engine speed.

Download the engine manual and take a look through section 3-50 (fuel system- governor).

If you put your foot down in neutral, you should safely reach the preset max engine speed.
If you're driving flat out at 45 and dip the clutch, does the engine speed up or not?

 

[Joe45]

Hard to tell in the video but the engine rpm sounds a lot lower than mine at 60mph.

Could be that someone messed with the governor settings and reduced the max engine speed.

Download the engine manual and take a look through section 3-50 (fuel system- governor).

If you put your foot down in neutral, you should safely reach the preset max engine speed.
If you're driving flat out at 45 and dip the clutch, does the engine speed up or not?

I'm gonna have to check on that. Thanks!
Where can I download the engine manual?

 

[Joe45]

Found it!

 

[45Dougal]

One thought..do you have a dipstick on your injection pump? I think yours should be plumbed in to use the engine oil, but mine needs separate oil which is a bit critical to its operation..

 

[Joe45]

One thought..do you have a dipstick on your injection pump? I think yours should be plumbed in to use the engine oil, but mine needs separate oil which is a bit critical to its operation..

I will have to see. I don't even know where to start looking right now.

 

[fjwagon]

I picked up a SA250, I aired up the tires but ran 55/60 mph with no issues on I10. That is a lot weight for just being strapped down. This particular welder weighs about 2000 pounds. I know it's not the same as pulling 4000 lbs. Anyhow, hauled it home no issues. I have taken concrete to the landfill again with no issues. On that that load I almost felt guilty for loading it down with so much wieght. Truck was squatting pretty good. The truck was following the ruts on the road. I would be interested to know the compression readings on your engine. I agree these engines are slow to pick up speed but once they reach their happy place, they will run and run. Mine seems to be fine around 60-65. It can handle 70 but I don't like to run the engine that fast. Don't think Toyota intended them to run them on the freeway....but we do.