BJ70 Birfield/Longfields

[FJoyBJoy]

Hi,
I need help from the 70 series cruiserhead.

Q: Will Longfields 30 splines kit (2 inner & 2 outer (birf)) for FJ40 will fit in my 1985 BJ70 cdn spec.

Q: Will LongfieldSuperAxle Hub Gear for FJ40/FJ60/4Runner will fit in my BJ70.



Story:

I'm building a BJ70 for off-roading purpose. It's my second one. My first one was equipped w/ 2 no-spin, 4,56:1 and Newfields by CV-unlimited.

Here I am with my new project, I've order 2 ARB air locker, 4,56:1 and I'm about to order beefy birfield. CV-Unlimited have stop the production of the Newfields (wich were fitting fine in my 1st BJ70). I don't trust the Marfield since I've broke them on my first Cruiser in the second trail they've blaze.

My choice is set on Longfields 30 splines by LongFieldSuperAxles. But now, I'm stick with fitting concern.

A guy from the Quebec french forum told me that he put axle shaft from a BJ70 and install them in his BJ42. He said that they are exactly the same axle (length, diameter, splines...). I've search on toyodiy.com for the parts number on front axle shaft for 1985 BJ70 vs a 1981 FJ40. They both have the same parts number. Inner RH 43411-60020, Inner LH 43412-60020, Shaft Drive (Birf) 43405-60015.

On the other hand, on cruiserfaq.com I've read :"70 Series axles are 20mm wider than 40 series".

If the inners and the outer of a 40 and a 70 series are the same parts, where the 20 mm width difference is?

I've search on IH8MUD and haven't find any answer for my concern. Maybe some tracks of anwser in that post but it is not clear for me. https://forum.ih8mud.com/70-series-tech/86256-longfield-newfield-bj70-tech-information-too.html


If the LH inner of the FJ40 is too short and the LH inner of the FJ60 is too long for my truck, will the 30 spline Longfield will fit my stock inner axle?

Is there any other product to get beefy birf for my BJ70?

Thank everybody and I apologize for my poor english. Hope you have understood everything.

 

[Greg_B]

The axle tube on the BJ7* is supposed to be slightly longer then the tube on the BJ4* series.

The front right and left inner axles, and birfields are the same, as you have seen with the part number comparisons.

The locking hubs are the same between the 1980's 4*/6*/7* series.

 

[coldtaco]

As I understand it the long shaft is different length from the 40 and 60 series. I got a set from Longfield and got the long shaft from Japan4x4 and the short side from Longfield and the outer parts/shafts. So I got one piece from Japan4x4 and the other 3 from Bobby Longfield. If you tell Bobbly your situation and that you are getting the one long piece from Japan4x4 he will sell you a incomplete set, at least he did for me.

 

[FJoyBJoy]

Thank Greg and coldtaco!

I've checked at the dealer and the inner & outer axle are the same on a BJ70 and a FJ40 just as Greg told me in his answer.

I'll order FJ40 Longfields set for my BJ70 and keep you informed when I'll get them and proceed with the installation. If it's not working, I will at least use the long's outer axles.


There is something that I still don't understand. How the BJ70 axle tube can be wider than the FJ40 axle but the both use the same inner part? I wonder it could be in the diff, maybe the side gears are a bit farther of the r&p... but the 40 and the 70 use exactly the same diff...

Someone here is less dumb than I and can explane that difference?

 

[FJoyBJoy]

Digging out and old post.

I've been out of the forum for a long time. I'll try to fix that in the future ;o)

I've receive two private messages asking me what happen with the Longfield in BJ70.


Well, it works!

The axle housing is slightly longer on a BJ70 than on a BJ4* but the inner and outer axle shaft has the same lenght. They're just not as deep into the diff in BJ70 than in a 40.

The Longfield Hub gears also fits in the BJ70.

 

[sadam_husain]

Digging out and old post.

I've been out of the forum for a long time. I'll try to fix that in the future ;o)

I've receive two private messages asking me what happen with the Longfield in BJ70.


Well, it works!

The axle housing is slightly longer on a BJ70 than on a BJ4* but the inner and outer axle shaft has the same lenght. They're just not as deep into the diff in BJ70 than in a 40.

The Longfield Hub gears also fits in the BJ70.

http://www.fjcruiserquebec.com/MGalleryItem.php?id=422

Yep x2 I put FJ40 30 spline longs in my FJ75, when I pulled the FJ75 axles and CVs and compared them to the longs they were identical lengths. My FJ75 is a 1985 model and I was told they are different after 1990 but I dunno that might be the models with the smaller 8" diffs?

 

[Radd Cruisers]

If you really need help with this, then Carl at JustDifferentials in Washington state is very knowledgeable with Land Cruisers. We sell their parts in Canada, or you can call Carl directly.

He carries chromo birfs, axle shafts, etc. All really nice quality stuff.

~John

 

[Tapage]

My FJ75 is a 1985 model and I was told they are different after 1990 but I dunno that might be the models with the smaller 8" diffs?

at least here yes .. all Cruiser pre 90 came with front low pinion standard rotation 9.5 .. and post 90 70 series and 80 series came with hi pinion reverse cut 8"

Although 70 series used small birf like 60 series even in post 90 models ..