7x Series Front Axle Tech Question - Early vs Late Style (1 Viewer)

[Will Van]

A few questions for the 7x series axle gurus:

I have a 1996 HZJ75 Land Cruiser with the 8” high pinion 3rd member front axle (similar to the 80 series).

For a variety of reasons, I am swapping to the early-style (1984 - 1989) 7x series axle with the larger 9.5” 3rd member. I already sourced a 1988 axle housing from @cruiseroutfit (thanks Kurt!).

My question is, to complete the axle, what parts can I source used from other Land Cruiser series’, what parts will swap over from my current axle, and what parts will I need to source new?

I think a set of used 9.5” 3rd members from a 60 series will swap in. And I think used 40 series axles/birfs will swap over.

Will the spindles, manual locking hubs, brakes, and steering knuckles from my current axle swap to the early axle?

Assuming I can source the used 60 series 3rd and 40 series axles/birfs, then I would just need to purchase a knuckle rebuild kit and diff gasket? Is that correct?

Thanks!

 

[RHINO]

If it helps, my 88 75 series is all 60 series for the front axle, which is also 40 and 55 series sans hubs and backing plates/brake lines.

I may be wrong but I don't think you can use a single part from that high pinion axle

 

[Will Van]

If it helps, my 88 75 series is all 60 series for the front axle, which is also 40 and 55 series sans hubs and backing plates/brake lines.

I may be wrong but I don't think you can use a single part from that high pinion axle

I thought the knuckle hardware would swap over from the early to late style axle housings, as long as you kept the assemblies generationally consistent. i.e. “early” knuckle with “early” hub/spindle.

For the axles, Cruiser Outfitters has replacement axles listed as:

• Fits 9/1975 - 1990 4x/55/7x Series w/Disc Brakes
• Fits 8/1980 - 1/1990 60/61/62 Series w/Disc Brakes

That led me to believe that 60 series axles would not work because they are a separate part number.

But maybe it has to do with hub splines? And because you used 60 series axles and 60 series hubs, it works?

 

[RHINO]

Not sure on all the particulars and you'll get some better answers.

Just figured I'd give you a direction to start looking and comparing.

Pretty much everything I ordered to rebuild my 1988 75 series front axle has been 60 series parts.

Edit: keep in mind I do alot of things considered odd by this community, like getting my overhead dome light from a camry in a junkyard, perfect fit and only a purist would notice

 

[rick_d]

Why are you switching?
I think most of the ‘96 parts won’t fit.
Short side 60 series inner fits pre 1991. 70 tube. Long side is 1981 40 ok or just get a 70).
Be warned, the big diff might impact your oil pan if you have the wrong step.

 

[Broski]

Why are you switching?
I think most of the ‘96 parts won’t fit.
Short side 60 series inner fits pre 1991. 70 tube. Long side is 1981 40 ok or just get a 70).
Be warned, the big diff might impact your oil pan if you have the wrong step.

I wonder why the switch as well
It's my understanding that the 8" is just as strong as the 9.5 except in reverse
The extra ground Clearance of the 8" at the def and driveshaft are a big plus in my eyes

 

[Will Van]

Why are you switching?
I think most of the ‘96 parts won’t fit.
Short side 60 series inner fits pre 1991. 70 tube. Long side is 1981 40 ok or just get a 70).
Be warned, the big diff might impact your oil pan if you have the wrong step.

I wonder why the switch as well
It's my understanding that the 8" is just as strong as the 9.5 except in reverse
The extra ground Clearance of the 8" at the def and driveshaft are a big plus in my eyes

I’m hesitant to answer this question because I don’t want to derail the thread into a debate.

But I’m switching because I think the 9.5” is stronger than the 8” high pinion AND I want to switch to 3.7 diff gears, which are way more common on the 9.5” 3rd (hell, you can find them used from a 60 series).

But I digress. Thanks for the info on the swap.

 

[Broski]

My apologies for the derail, it was truly meant as a question and I have no experience with the 9.5 so I would not know.

Following this thread because I want to learn the difference in the axles.

 

[Will Van]

My apologies for the derail, it was truly meant as a question and I have no experience with the 9.5 so I would not know.

Following this thread because I want to learn the difference in the axles.

No worries!

 

[coldtaco]

As far as I know all 60 series parts fit to the 70 w/ the 9.5 diff. The only thing that will NOT fit is either the short or long drive shaft. I want to say the short one but can’t remember anymore.

 

[Will Van]

As far as I know all 60 series parts fit to the 70 w/ the 9.5 diff. The only thing that will NOT fit is either the short or long drive shaft. I want to say the short one but can’t remember anymore.

Thanks for the info. Just to clarify, either the short or the long driveshaft from a 60 series will not fit, correct?

It would make sense if the short driveshaft from a 60 series did not swap, because the bolt patterns on the front pinion flange/t-case is different on the 8” HP.

 

[rick_d]

you can order 3.70 and 3.73 gear sets from UAE sources for high pinion.

I myself did 3.90 gear set (high pinion front) after running standard 4.11 in cable lockers (which really are 100% guaranteed to hit the pan with 2" lift on1hdt).

I saw a number of broken reverse cut diffs at ENS industrial. Miners often started the truck at -50C and dropped the clutch. They would then send diff to the shop and say "this truck is new and this broke under warranty period".

LONG SIDE 60 SERIES INNER AXLE will not fit a 70 series tube.
1981-1984 FJ40 AND 1985-1989 J70 series long side do fit.
there is a slight difference long side 1976-1980 FJ40 inner axle.
long spline factory part is obsolete part number.

 

[Will Van]

you can order 3.70 and 3.73 gear sets from UAE sources for high pinion.

I myself did 3.90 gear set (high pinion front) after running standard 4.11 in cable lockers (which really are 100% guaranteed to hit the pan with 2" lift on1hdt).

I saw a number of broken reverse cut diffs at ENS industrial. Miners often started the truck at -50C and dropped the clutch. They would then send diff to the shop and say "this truck is new and this broke under warranty period".

LONG SIDE 60 SERIES INNER AXLE will not fit a 70 series tube.
1981-1984 FJ40 AND 1985-1989 J70 series long side do fit.
there is a slight difference long side 1976-1980 FJ40 inner axle.
long spline factory part is obsolete part number.

Great intel, thank you.

 

[Will Van]

Also, you don’t have to go to UAE to source 8” HP 3.73 diff gears. They are available from Nitro: Nitro Gear & Axle Toyota 8" 3.73 Ratio Reverse Ring And Pinion | T8R-373R-NG - https://www.vividracing.com/toyota-inch-373-ratio-reverse-ring-and-pinion-nitro-gear-and-axle-p-151886719.html

 

[Radd Cruisers]

I have the 3.73 8" and 9.5" gears in stock....

Search results for differential

RADD Cruisers 4WD Ltd. is a British Columbia-based automotive business offering a diverse range of service kits and repair parts for Toyota Land Cruisers as wel

radd-cruisers.shoplightspeed.com

~John

 

[Will Van]

I have the 3.73 8" and 9.5" gears in stock....

Search results for differential

RADD Cruisers 4WD Ltd. is a British Columbia-based automotive business offering a diverse range of service kits and repair parts for Toyota Land Cruisers as wel

radd-cruisers.shoplightspeed.com

~John

Thanks, but I’m looking to swap to the 9.5” diff axle housing. Any idea if my knuckles from the 8” will swap over to the 9.5” axle housing? Can I use 40 series axle shafts?

 

[Radd Cruisers]

Thanks, but I’m looking to swap to the 9.5” diff axle housing. Any idea if my knuckles from the 8” will swap over to the 9.5” axle housing? Can I use 40 series axle shafts?

The knuckles are somewhat different. Some of the parts will fit, others not.

The 70 and 40 are very close in width, and the front shafts should easily interchange from a 40 to a 70. The 70 is a bit wider on one side.

It would be more cost effective to obtain 40 or 60 series parts for the knuckles - typically they are plentiful.

As far as strength goes, yes, the 9.5 will be stronger than the 8”, but I honestly don’t think it’s worth the effort to swap out the 8” front end for just the strength advantage.

I’ve owned my fair share of HZJ7x series and they are not weak trucks.


~John

 

[Will Van]

The knuckles are somewhat different. Some of the parts will fit, others not.

The 70 and 40 are very close in width, and the front shafts should easily interchange from a 40 to a 70. The 70 is a bit wider on one side.

It would be more cost effective to obtain 40 or 60 series parts for the knuckles - typically they are plentiful.

As far as strength goes, yes, the 9.5 will be stronger than the 8”, but I honestly don’t think it’s worth the effort to swap out the 8” front end for just the strength advantage.

I’ve owned my fair share of HZJ7x series and they are not weak trucks.


~John

10-4. Thanks for the info!

If I did install 3.73 R&P in my 8” housing, what other components would I need? Install kit?

 

[Loober]

@Radd Cruisers ordered sets of 3.73 gears for my 77 last night, looking forward to life in lower rpms.

 

[Loober]

10-4. Thanks for the info!

If I did install 3.73 R&P in my 8” housing, what other components would I need? Install kit?

Expanding more on that, I doubt any of us will be entering our vintage 70 series into a King of the Hammers competition, aside from that the typical wheeling 99.99% that most of us would do, these 8" axles can easily handle. Heck I did the rubicon and many other tough trails with my IFS tacoma on a 7.5" clamshell, that held up fine. The lower hanging 9.5" will be a more detriment than any strength advantages it may have.