1982 BJ-42 Towing Capacity??

[45jim]

BJ42 Towing Capacity

I was searching to confirm this exact data as I have to move across Canada this summer and want to tow a trailer behind my '84 BJ42.

I happen to have the orignal owners manual for my '84 and it may shed some light on this discussion, it states:

Trailer Towing:

Trailer weight plus its cargo must not exceed a total of 2500lbs (1135kg). Exceeding this weight is dangerous.

The gross combination weight (sum of your vehicle weight plus its load and the trailer weight plus its load) must not exceed 7000lbs (3175kg) for Hardtops (BJ42LV) and 7500lbs (3400kg) for station wagons (BJ60LG).

Also, the gross vehicle weight must not exceed the Gross Vehicle Weight Rating (GVWR) indicated on the Certification Regulation Plate. The gross vehicle weight is the sum of weights of the unloaded vehicle, driver, passengers, lugage, hitch and trailer tongue load. It also includes the weight of any special equipment installed on your vehicle.

Further, the load on either the front or rear axle resulting from distribution of the gross vehicle weight on both axles must not exceed the Gross Axle Weight Rating (GAWR) listed on the Certification Regulation Plate.

While the handbook does not explain how these numbers were determined certain deductions can be made from the information:

1. Engine performance (HP and torque) have nothing to do with towing capacity ratings as the BJ60 has the same drivetrain as the '42 but it has 500lbs more capacity probably due to a longer chassis wheelbase (higher stability when towing) and since there is no change in the rating for a gas or diesel engine (significantly different engine performance) this again confirms that chassis is the key element in rating determination.

2. I was looking at towing a U-Haul (yeah, I know) 5' x 10' tandem axle trailer. It has surge brakes and has an empty weight of 1,250lbs giving me a useful capacity of 1,250lbs. Fine for my tools and motorcycle, and safe.

3. There is no question that Landcruisers can carry and tow much more than they are rated for. The ratings are engineered to be on the safe side and the company's legal department would want to have it as low as possible (while still useful) to limit liability. There is no change in the tow rating or mention of trailer brakes. I believe these standards are set by the Government and enforced of trailer manufacturers and users.

4. As an aside, we had some green painted civilian trucks in the Army when I wore fashionable green, and they had a 25% higher tow rating than the same truck with shiny paint. When I asked the manufacturers rep why, he told me that he military rating was factual and tested while the civilian ones were de-rated to limit liability and "to save the public from themselves".

Perhaps this helps?

 

[crushers]

the added weight of the wagon in your assumption wouldn't be the added weight of a full size wagon (500 lbs heavier than the same year hard top) could it?

since the engines are the same in both then why would they differenciate between the two?

but alas there is a problem with your assumption... the Bj42 has 4.11 gearing and the wagon has 3.70 so if this is the case then diff gears has no bearing on tow rating either... which is total bull**** since you can not tow the same weight of trailer behind a 4.88 geared truck the same as the same truck configuration with 2.73 gearing...

I was searching to confirm this exact data as I have to move across Canada this summer and want to tow a trailer behind my '84 BJ42.

The gross combination weight (sum of your vehicle weight plus its load and the trailer weight plus its load) must not exceed 7000lbs (3175kg) for Hardtops (BJ42LV) and 7500lbs (3400kg) for station wagons (BJ60LG).


1. Engine performance (HP and torque) have nothing to do with towing capacity ratings as the BJ60 has the same drivetrain as the '42 but it has 500lbs more capacity probably due to a longer chassis wheelbase (higher stability when towing) and since there is no change in the rating for a gas or diesel engine (significantly different engine performance) this again confirms that chassis is the key element in rating determination.


Perhaps this helps?

 

[Dougal]

I was searching to confirm this exact data as I have to move across Canada this summer and want to tow a trailer behind my '84 BJ42.

I happen to have the orignal owners manual for my '84 and it may shed some light on this discussion, it states:

Trailer Towing:

Trailer weight plus its cargo must not exceed a total of 2500lbs (1135kg). Exceeding this weight is dangerous.

The gross combination weight (sum of your vehicle weight plus its load and the trailer weight plus its load) must not exceed 7000lbs (3175kg) for Hardtops (BJ42LV) and 7500lbs (3400kg) for station wagons (BJ60LG).

Also, the gross vehicle weight must not exceed the Gross Vehicle Weight Rating (GVWR) indicated on the Certification Regulation Plate. The gross vehicle weight is the sum of weights of the unloaded vehicle, driver, passengers, lugage, hitch and trailer tongue load. It also includes the weight of any special equipment installed on your vehicle.

Further, the load on either the front or rear axle resulting from distribution of the gross vehicle weight on both axles must not exceed the Gross Axle Weight Rating (GAWR) listed on the Certification Regulation Plate.

While the handbook does not explain how these numbers were determined certain deductions can be made from the information:

1. Engine performance (HP and torque) have nothing to do with towing capacity ratings as the BJ60 has the same drivetrain as the '42 but it has 500lbs more capacity probably due to a longer chassis wheelbase (higher stability when towing) and since there is no change in the rating for a gas or diesel engine (significantly different engine performance) this again confirms that chassis is the key element in rating determination.

2. I was looking at towing a U-Haul (yeah, I know) 5' x 10' tandem axle trailer. It has surge brakes and has an empty weight of 1,250lbs giving me a useful capacity of 1,250lbs. Fine for my tools and motorcycle, and safe.

3. There is no question that Landcruisers can carry and tow much more than they are rated for. The ratings are engineered to be on the safe side and the company's legal department would want to have it as low as possible (while still useful) to limit liability. There is no change in the tow rating or mention of trailer brakes. I believe these standards are set by the Government and enforced of trailer manufacturers and users.

4. As an aside, we had some green painted civilian trucks in the Army when I wore fashionable green, and they had a 25% higher tow rating than the same truck with shiny paint. When I asked the manufacturers rep why, he told me that he military rating was factual and tested while the civilian ones were de-rated to limit liability and "to save the public from themselves".

Perhaps this helps?

An excellent first post, welcome to Mud.

 

[45jim]

Diff gearing has nothing to do with it....

I believe you have a problem understanding this issue as you jump from engine to frame and now to axle gearing to support your statements. I guess as each one is disproven you grasp for something else, like a drowning man.

Let me throw you a rope.

It really quite simple when you want to talk about "pulling power" you are not talking about towing capacity as they are unrelated.

Towing capacity is related to the strain the chassis will take without distorting permanently; as the weight of the trailer is applied to the chassis on one of its weakest areas, the centre of the rearmost crossmember. This will determine the acceptable load that can be applied over and over without damage.

Pulling power is the ability to apply the engine torque multiplied by gearing through the suspension and tires to the ground.

When you see truck ratings for say a regular F-150 being "X" and then another value "X+" when you buy the towing package the chassis is not being reinforced they just are providing heavier duty parts so the thing will last until the warranty expires.

 

[crushers]

Jim, old buddy, i miss you guys in Calgary already...

here is your post:
Trailer Towing:

Trailer weight plus its cargo must not exceed a total of 2500lbs (1135kg). Exceeding this weight is dangerous.

The gross combination weight (sum of your vehicle weight plus its load and the trailer weight plus its load) must not exceed 7000lbs (3175kg) for Hardtops (BJ42LV) and 7500lbs (3400kg) for station wagons (BJ60LG).



here is the post from Wimpie in belgium:
BJ40

--------------------------------------------------------------------------------

I have 2 bj40's and on the papers it says the car weighs 1560kg.
Max load load (car included) 2300kg meaning aprox 640kg loading in the car.
And max load pulling (also car included) 6300kg

IWhen you see truck ratings for say a regular F-150 being "X" and then another value "X+" when you buy the towing package the chassis is not being reinforced they just are providing heavier duty parts so the thing will last until the warranty expires.

Now, you are saying a one ton towing capacity is acceptable and Wimpie is saying his truck is rated for 4 ton towing.

and BJ42 from Norway posts:
In Norway one can get a paper form the official Toyota importer listing the BJ42 towing capasity at 3000kg (or 6600lbs),

now, i know LC frames and they are the same from 1979 to 1984 so my question is this. since engineers work from the same set of values then how can there be a 3 FRIGGIN TON difference in ratings?

then Dougal, in all his wisdon states:
Tow rating's are about the chassis, brakes and suspension strength.

hold on, if you are saying tow rating is about frame strength (and you are an engineer) and Dougal is a self proclaimed engineer, then who is right? is it just frame strength or does the chassis components come into play as well...if the chassis components come into play then my comment about diff gears IS relevant to the discussion.

as for being a man at the end of my rope, the question at the beginning of this thread was towing capacity. for most of us no-minds, towing capacity is "what can my truck safely pull". the blokes that have been around these trucks for decades have answered... not a hell of a lot.

even Toyota says not over a ton and a quarter in your book.

but then we have engineers that say you can pull 4 ton safely... i still say that is pure, unmodified steer manure.

in the end, common sense should come into play. no matter what some bloke behind a keyboard types, no matter what some engineer that was paid to say what he says... it is the driver of the towing vehicle that has to live with his descision... and that discision could cost him his life and or those that he hits...

Jim, i understand what you are saying. i just can not fathom a different set of rules and values for engineers in different parts of the world.

common sense...too bad they can't teach THAT in school. most engineers would fail that course.

 

[Dougal]

now, i know LC frames and they are the same from 1979 to 1984 so my question is this. since engineers work from the same set of values then how can there be a 3 FRIGGIN TON difference in ratings?

Quite simple. Different countries have different legislation regarding towing. The owners handbooks for each market reflect that.

then Dougal, in all his wisdon states:
Tow rating's are about the chassis, brakes and suspension strength.

hold on, if you are saying tow rating is about frame strength (and you are an engineer) and Dougal is a self proclaimed engineer, then who is right? is it just frame strength or does the chassis components come into play as well...if the chassis components come into play then my comment about diff gears IS relevant to the discussion.

You've read that wrong. The "Chassis" is not just the frame, the chassis is the whole structure of the vehicle, this includes all stressed components.
Bad assumptions leading to the wrong conclusion. Probably why you didn't get the difference between a 2wd and 4wd chassis earlier in this thread.

 

[crushers]

REALLY??

chas·sis (shs, chs)
n. pl. chas·sis (-z)
1. The rectangular, usually steel frame, supported on springs and attached to the axles, that holds the body and motor of an automotive vehicle.

chassis = frame

supported by springs and attached to the axles.

Types of Chassis
Ladder Chassis:
Ladder Chassis is considered to be one of the oldest forms of chassis that is still used by most of the SUVs till today. As its name connotes, ladder chassis resembles a shape of a ladder having two longitudinal rails inter linked by several lateral and cross braces




different legislation makes no difference to the integrity of the frame and what it can handle. it is an engineering calculation...is it not?

huge difference between 1 ton tow and a 4 ton tow...

 

[crushers]

okay, think that statement through...
you are talking stress loads on components during towing, correct?

the frame will be stressed if the load is too heavy and the shock load will affect the attachment point(s)

but, if the max rated tongue weight is the same for both the 1 ton configuration AND the 4 ton configuration then the springs are not stressed AND the axle housing is not stressed.
it is my understanding that you want 10%-15% of the trailer weight on the tongue (1 ton =300 lbs, a 3 ton = 900 lbs and a 4 ton = 1200 lbs (which BTW the factory rear springs of a BJ42 are not designed to handle)) a stock BJ42 has a tongue weight max of 770 lbs (350 kg).

if the trailer has self braking then the brakes are not stressed

BUT

what is stressed?
the drivetrain is the stressed portion. if the vehicle is equiped with highway gears instead of towing gears that stress is transmitted back through the drivetrain through ALL the components in the vehicle. THAT is the stress factors.

You've read that wrong. The "Chassis" is not just the frame, the chassis is the whole structure of the vehicle, this includes all stressed components.
.

 

[joshoisasleep]

OK I've actually totally lost who was arguing what in this thread?? There's lots of interesting info but I can't figure out what arguments they're all trying to support?

 

[canucksafari]

OK I've actually totally lost who was arguing what in this thread?? There's lots of interesting info but I can't figure out what arguments they're all trying to support?

maximum towing capacity verses safe and comfortable towing ability.

or

mechanic verses engineer

or

reason verses logic

or

common sense verses book sense

or

ego verses ego

At any rate its been ... .

 

[Dougal]

REALLY??

chas·sis (shs, chs)
n. pl. chas·sis (-z)
1. The rectangular, usually steel frame, supported on springs and attached to the axles, that holds the body and motor of an automotive vehicle.

chassis = frame

supported by springs and attached to the axles.

Types of Chassis
Ladder Chassis:
Ladder Chassis is considered to be one of the oldest forms of chassis that is still used by most of the SUVs till today. As its name connotes, ladder chassis resembles a shape of a ladder having two longitudinal rails inter linked by several lateral and cross braces

different legislation makes no difference to the integrity of the frame and what it can handle. it is an engineering calculation...is it not?

huge difference between 1 ton tow and a 4 ton tow...

Your definition is outdated, try applying it to a monocoque vehicle and you'll see the problem.

Local legislation often restrict capacity below the manufacturers limits. This is not a difficult concept, it is called bureaucracy.

The stress encountered by the drivetrain is no greater than during unloaded acceleration. The stress encountered by the chassis and brakes are vastly different. Using overrun brakes (surge brakes) and even fully braked trailers still puts more load on the towing vehicles brakes.

 

[crushers]

a unibody is still just the frame (in this case including the fame sheet metal) but still does not include the suspension, etc...

if you honestly believe it is safe to tow 4 ton behind a BJ42 at highway speeds then there is no more to discuss. you are an idiot, simple as that.

Your definition is outdated, try applying it to a monocoque vehicle and you'll see the problem.

Local legislation often restrict capacity below the manufacturers limits. This is not a difficult concept, it is called bureaucracy.

The stress encountered by the drivetrain is no greater than during unloaded acceleration. The stress encountered by the chassis and brakes are vastly different. Using overrun brakes (surge brakes) and even fully braked trailers still puts more load on the towing vehicles brakes.

 

[Dougal]

if you honestly believe it is safe to tow 4 ton behind a BJ42 at highway speeds then there is no more to discuss. you are an idiot, simple as that.

So just to recap.
The collective brains-trust at Toyota rate their vehicle to tow 4 ton (where laws allow of course, fully braked trailer etc), a mechanic in canada is arrogant enough to tell them they're all idiots?

 

[canucksafari]

It wouldn't be the first time would it?

Not to slander the engineering profession. One of my best friends is one. But I have seen enough multi million dollar mess ups by engineers to know that they often get it wrong - just like a number of mechanics I have dealt with over the years. And even once and a while - especially when the wife is looking - I get some things wrong too.

 

[Dougal]

Having been in a 40 series towing 3+ ton farm implements, I'm squarely on Toyota's side with this one.

What's it going to do, explode if you hook up a trailer with more than crusher's predicted maximum?

 

[joshoisasleep]

Was just hanging out with an irish engineer who told me proudly of intentionally messing with an undesirable project in such a way that he looked good but it cost the english company doing it millions of pounds extra. hah!

 

[crushers]

oh my GOD, you where IN a 40 that towed 6000 lbs of steel... and that is your proof?

and was that through the mountains passes? up and down steep hills? with sharp bends to negotiate? and was that at 110 km/hr? was that down gravel roads at 80 k/h? (and did the farm implement have trailer brakes built in? if not then what the hell where you doing towing it behind a 42?)
you experienced all the possible road conditions and driving conditions at highway speeds in your single run? AMAZING.

nope, it won't expload but (if you had actually read one of the earlier posts) since a BJ42 has a tongue weigth of 350 kg (770 lbs) that 4 ton tow rating EXCEEDS the max (min 10% (800 lbs) of the trailer weight with a prefered 15% (1200 lbs)) designed into the 42. this will cause unsafe driving characteristics, unsafe loading of the rear springs and axle bearings since they were not designed (and rated an engineer) to sustain this load over long distances.

and

YOU might advise incorrectly and cause a death or harm due to one of the visiters to this forum and thread as well as cratering his 3B in a 92 hp, 90" wheel based, 3900 lb vehicle, pulling 8000 lbs of payload at highway speeds.

so yes, you are an idiot to agree with Toyota's claim in this instance.

Having been in a 40 series towing 3+ ton farm implements, I'm squarely on Toyota's side with this one.

What's it going to do, explode if you hook up a trailer with more than crusher's predicted maximum?

 

[Dougal]

nope, it won't expload but (if you had actually read one of the earlier posts) since a BJ42 has a tongue weigth of 350 kg (770 lbs) that 4 ton tow rating EXCEEDS the max (min 10% (800 lbs) of the trailer weight with a prefered 15% (1200 lbs)) designed into the 42. this will cause unsafe driving characteristics, unsafe loading of the rear springs and axle bearings since they were not designed (and rated an engineer) to sustain this load over long distances.

I don't know where you got the 10-15% tongue load from, but probably the same place you found the 300hp 70 series with the disc brakes all round and the 2wd 70 series.

Maybe you've never seen a four wheeled trailer or just don't know how to load them.

 

[kim]

I don't know where you got the 10-15% tongue load from, but probably the same place you found the 300hp 70 series with the disc brakes all round and the 2wd 70 series.

Maybe you've never seen a four wheeled trailer or just don't know how to load them.

Perhaps terminology is confusing people here. I believe that the four wheeled 'trailer' referenced above is actually a wagon, in North American terms and wagons don't have any appreciable tongue weight. All trailers, when loaded correctly should have about 10 percent or the loaded weight on the tongue.

 

[brownbear]

Wayne.....I think your forgetting your arguing against a wall.

4 tons in NZ might be a hell of a lot different than in North America. I can tow 10k lbs on small roads. Our tow ratings in NA are for interstates that encompass mountain passes and massive prairies.

From my experience towing with a 3B. I found the limit or close to it. I towed 810 kg(1782lbs) and my truck weighed 3020 kg(6644lbs). I towed 12,500 kms on my last trip across the country. My weight was confirmed on scales. I drove the vail pass(11,150 feet) and across the prairies in massive winds.

Lets say I found the limit. I may have been able to squeak a little more. But not much. My trailer had no brakes, but I was fine on every "mountain" I encountered.

Can a forty be able to tow 4 tonnes, sure maybe in a city or on an island. Whatever your "country" thinks it can do.

Texas, you can tow 3k lbs for short distances safely as long as your not on fast roads and in hills.