LJ vs BJ/FZJ 70 Series Frame (1 Viewer)

[MrSAfro]

I know the LJ78, the original Prado / Light Duty Land Cruiser has a lighter duty suspension, axles and drivetrain. But, those could easily be upgraded to 80 series components.

My main question is, was the chassis / frame also made lighter duty or from lighter / thinner steel?

I have an opportunity to buy one, and want to upgrade it to heavier duty drivetrainand axles from an 80 series, but if the chassis rails are not as strong as the heavy duty 70 series, it would not be worth it.

 

[Gun Runner 5]

The "heavy duty" guys are going to tell you that the LJ78 frame is made of tinfoil while the "light duty" guys are going to tell you it's made from the same metal they use on nuclear submarines. The truth is in the middle somewhere.

 

[hoser]

I don't know if the steel is the same thickness but the LJ's are fully boxed as well. My guess, it is of similar construction.

You can see close-ups of the frame here.

 

[coldtaco]

only difference also is the front radiator/front fender mounts, LJ is wider I think, or is it narrower? Probably wider.

 

[GTSSportCoupe]

Having been under both heavy duty and light duty 70's, I'd say the frame is easily the same strength (Note, I'm talking 1990+ models here - they had a number of strength upgrades over the earlier years). What I can tell you for sure is it is a heck of a lot stronger than 40 and 60 series frames.

@coldtaco is right; the main difference is in the front most cross member and mounting points for the fenders and radiator etc.

You should know that front axles/birfields/spindles/hubs/bearings/knuckle/brakes are all the same part numbers as the heavy duty 70 series. The front axle housing is different however (to suit the coil suspension).

The T-case is also the same as the heavy duty 70 series. Also the A343F and R151F transmissions are found in various heavy duty land cruisers.

So really it's the engine and rear axle that are truly light duty.

Depending on your use, the rear axle is probably plenty strong enough. I tow a 16' camper every year and my total camper/truck weight come out to 9000lb. Towed year after year and never had any problems with the rear axle (or anything other than the engine for that matter).

However if you are going to be doing really heavy wheeling with 35"+ tires full locked etc.; the diffs may not stand up.

Put a 15BFT/H55 into a 1990 LJ7x and call it a day.

Edit: one last thing. I've seen 80 series axles under 70 series, and they look weird IMHO....too wide.

 

[MrSAfro]

Having been under both heavy duty and light duty 70's, I'd say the frame is easily the same strength (Note, I'm talking 1990+ models here - they had a number of strength upgrades over the earlier years). What I can tell you for sure is it is a heck of a lot stronger than 40 and 60 series frames.

@coldtaco is right; the main difference is in the front most cross member and mounting points for the fenders and radiator etc.

You should know that front axles/spindles/hubs/bearings/knuckle/brakes are all the same part numbers as the heavy duty 70 series. The front axle housing is different however (to suit the coil suspension).

The T-case is also the same as the heavy duty 70 series. Also the A343F and R151F transmissions are found in various heavy duty land cruisers.

So really it's the engine and rear axle that are truly light duty.

Depending on your use, the rear axle is probably plenty strong enough. I tow a 16' camper every year and my total camper/truck weight come out to 9000lb. Towed year after year and never had any problems with the rear axle (or anything other than the engine for that matter).

However if you are going to be doing really heavy wheeling with 35"+ tires full locked etc.; the diffs may not stand up.

Put a 15BFT/H55 into a 1990 LJ7x and call it a day.

Edit: one last thing. I've seen 80 series axles under 70 series, and they look weird IMHO....too wide.

Wow, to you and the rest. Awesome replies! I think I am going to go ahead and buy it, bit sick of the harsh bounce of the leaf spring 70s after 4 of them in various configurations. Want a coil sprung 70. Will upgrade engine first. Then use with driveline as is, and upgrade as it breaks.

 

[Previa Diesel]

As per GTS Sport Coupe above, the one LJ78 I saw torn down for parts I still regret not buying the rolling chassis for $200! It looked a hell of lot tougher than what is under my Tundra.

 

[GTSSportCoupe]

In Canada HZJ77's seem to be selling for $25,000-35,000CAD. LJ78's can be had for $2000-7000CAD. For anyone who can do their own wrenching/swaps, the LJ7x's are a heck of a good deal. I'd never spend that much to upgrade to a 1HZ and full floating rear axle. I'd just swap them in if I wanted them. I don't even like the 1HZ and would much prefer a direct injection engine. So even if I bought a HZJ77, I'd probably still swap the engine regardless. So why bother spending so much extra money to start?

I've seen a few 15BFT swaps in light duty 7x cruiser's now, and I think that is a heck of a great engine upgrade for the vehicle. Makes for a better final product than an HZJ77 IMHO. Other great diesel options are the 13BT, 14BT. Really any direct injection B engine. Fellow in the classifieds was selling Megacruiser 15BFT engine/trans with accessories for $4500USD! I'll probably be kicking myself later for not buying one.

 

[Previa Diesel]

I had a pristine 77 for a while. Impressive truck, and went quite well with the 1HZ I thought, even without a turbo. The truck was too heavy and suspension not responsive enough for use on ice or snow at higher speeds IMHO. OM617 would be my swap into an LJ78 I think, but then I'd take prefer simplicity and reliability over performance any day. That or 12HT, or maybe a Perkins.

 

[clintnz]

I know the LJ78, the original Prado / Light Duty Land Cruiser has a lighter duty suspension, axles and drivetrain. But, those could easily be upgraded to 80 series components.

My main question is, was the chassis / frame also made lighter duty or from lighter / thinner steel?

I have an opportunity to buy one, and want to upgrade it to heavier duty drivetrainand axles from an 80 series, but if the chassis rails are not as strong as the heavy duty 70 series, it would not be worth it.

The LJ chassis is plenty strong as noted above.

However if you think that the LJ78 axles can 'easily be upgraded to 80 series components' you are either a rockstar fabricator or in for a very rude shock. In the back the upper linkages & spring perches need to be moved inboard on the axle housing, 4x linkage mounts built onto the chassis, panhard bar modified, driveshaft modified....

The list for the front end will be similar. I used a Nissan GQ front axle - same width & ratio as 80 series but stronger in several ways.

More info in my build thread

Cheers
Clint

 

[wardharris]

In Canada HZJ77's seem to be selling for $25,000-35,000CAD. LJ78's can be had for $2000-7000CAD. For anyone who can do their own wrenching/swaps, the LJ7x's are a heck of a good deal. I'd never spend that much to upgrade to a 1HZ and full floating rear axle. I'd just swap them in if I wanted them. I don't even like the 1HZ and would much prefer a direct injection engine. So even if I bought a HZJ77, I'd probably still swap the engine regardless. So why bother spending so much extra money to start?

I've seen a few 15BFT swaps in light duty 7x cruiser's now, and I think that is a heck of a great engine upgrade for the vehicle. Makes for a better final product than an HZJ77 IMHO. Other great diesel options are the 13BT, 14BT. Really any direct injection B engine. Fellow in the classifieds was selling Megacruiser 15BFT engine/trans with accessories for $4500USD! I'll probably be kicking myself later for not buying one.

Price delta is reason we just bought an LJ 77 as a R&D rig to build for. Tank, rear bumper, suspension, motor/trans options all on the table with help from some friends.

And......it is a LHD

 

[AirheadNut]

Price delta is reason we just bought an LJ 77 as a R&D rig to build for. Tank, rear bumper, suspension, motor/trans options all on the table with help from some friends.

And......it is a LHD

View attachment 2542267

Is that the one that @SNLC imported a while ago? Looks really nice!

 

[wardharris]

Price delta is reason we just bought an LJ 77 as a R&D rig to build for. Tank, rear bumper, suspension, motor/trans options all on the table with help from some friends.

And......it is a LHD

View attachment 2542267

Is that the one that @SNLC imported a while ago? Looks really nice!

Nossir, not an Ian production, tho I would use/trust him completely. This one was sourced through Adam at Canary Island Rover as here 1991 Toyota Land Cruiser LJ77 LX - CANARY ISLAND ROVER - https://www.canaryislandrover.com/project/1991-toyota-land-cruiser-lj77-lx/

Thanks for the comment.