LJ78 axle swap

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I

I will NOT give up

10 Year 15 Year
Joined
Sep 22, 2007
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4
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22
Location
Fraser Valley
Hello all,
I am contemplating a project and i wonder if anyone else has done this or has any input to promote / discourage the idea.
While waiting for my Prado to come out of the shop after three months of the insurance company trying to figure out which way is up, i saw this JDM 80 sitting as a parts truck.
I know a local business that can convert the 80 axle leaf suspenseion to mount to my 78's coils.
The immediate advantages are the 80's manual locking hubs, factory cable lockers and full size diffs. My concern is will the 2.4 LT-E and tranny and t-case be enough, or am i going to have to transplant the 4.2 and running gear as well?
Are there any other concerns that a more experienced cruiserhead would caution me on?
Input appreciated...
 
first, the frotn diff of the 80 series is the same size and strength as your 78... no benifit there
the 80 has locking hubs? since when?
you are going from 4.9 gearing down to 4.11 gears in the 80 series diff
the 2LTE has enough problems moving the 78 down the road with stock gears let alone going to a high ratio
you can get factory rear elec locker for the 78
the tranny is the same one that is behind the V8 land cruiser (if auto) if manual it is the same as the ones in the mine trucks (different imput shafts) the t/case is your typical 2 peice.

so in the end you will end up with a full size rear diff...
in my books not worth the effort considering the smaller rear diff is plenty tough.
 
8X series

Sorry, may not be an 80 but an 8x.
It does have manual locking hubs and i am pretty sure it has the full size diff.
You are right about the 4.11s, not so good for the highway?
Was really excited about the idea of cable lockers,
How much/ hard would it be to install electric rear locker? I was told by the importer that i can get an LSD for the 78 for $1,800.
Thanks for your thoughts.
 
there are quite a few coming up as parts trucks that might have the Elocker in the rear, straight swap and get the elec wiring and the switch.

are you talking 1980 or the 80 series?
the 80 series never came with cable lockers...
 
the 80 series did not come out till 1990...
i would suggest you go look at the truck before you buy it...sounds like there is either some misinformation or the guy is BSing you..
 
I will NOT give up said:
now i have to go back and check with the guy... i was sure he said 80 series. i was also sure he said it had a 4.2 litre turbo.
it is RHD and 1988/89.
Click to expand...

Sounds like a HJ61
 
HJ61

Thank you Rosco, you are correct
What i was looking at was an HJ61, and it has a 4 litre turbo. If i can't get stuff like that right, i wonder if i should bother with modifications. But the dream is still alive, even if only in my head.

I am going to get my truck back this weekend (after 2.5 months) and then i can do some better checking, but probably someone here can tell me.
Will the 6 cyl, 4 litre engine fit in where the 2 LT-E is? What is the HJ61 engine called, please?
The HJ61 has an automatic tranny, is it even possible to find a manual one to fit?
Is fitting the engine, tranny, transfer case and axles from the HJ61 into the LJ78 going to be a logistical nightmare?:bang:
Can someone suggest a better modification for more power and locking differentials? (other than selling the Prado)
Many Thanks
 
12HT anything can be done with time and money.
locking diffs... air locker? *not my favorite) elocker rear only.

a PZ, HZ, 13BT can be done but extensive work is required.

recommend selling and buying what you desire "turn key:
 
What Wayne (crushers) said:D That being said, I am undergoing the exact project. First off, I would stay away from a normally asperated diesel living/driving in BC, I think that's where you live.
Second, I think a 13B-T swap would probably fit with your front end. A six cylinder will not have the room. I am in the process of installing a 1HD-T into a LJ-78 but I will have to use my "heavy duty" front end from my donor BJ-70, which has a longer nose. Other than that I think it will fit. I am still trying to decide on the axles as I have a set of full floater axles with cable lockers under my BJ-70 and trying to decide on what to do about them. Wayne says the 78 axles are as strong as 80 series so I should be alright with them, but I got these good full floater axles.
You being in Canada have better options than us in the US as to what we can get as far as 70 series cruisers, so I would probably sell the 78 and find what you want.
By the way, I still have a 13B-T and H55F for sale if you decide on tackling this.

Wayne, what options do I have for a front locker? I don't really want a air locker, but I want a selectable locker. Thanks.
 
I just put an ARB air locker in the front of my HZJ79 - 8 inch front end, no idea if I like it. I think a proplem that people might have with ARB up here is water contamination ffrom teh air compressor - so I added a manifold and air seperator to my air system. If the front end is th esame as mine or an 80 series then you can use an 80 series front e locker. I couldnt because of gearing issues.

Also, when installing your 1HD-t in your truck you can fit a 9.5 inch front end from your 70, but you will have to keep the tie rod in front of the dif - won't fit behind, and the diff will just clear the oil pan - I suspect you will have a lift kit so you will be alright.
 
beyond me... i have no idea what will work in the front of the 78, it is different from the 8* and the 7* HD series...

to be honest, i gave up caring about the LJ series a year or so back... love the ride, HATE the engine.
 
Louis
Can you explain what you mean by gearing issues with swapping in a 80 series 3rd member? Aside from the high pinion vs low pinion is there any reason a 80 3rd member will not fit? Does this matter? Can you use the 78 3rd member housing and swap in the 80 3rd w/ elocker inners? Do you know of any other options for a front locker that's selectable?
Thanks.
 
You just have to make sure that the gear ratio is the same. My HZJ79 is a 4.30, the 80 series is a 4.11 IIRC, not sure what the 78 is. I think the 78 rear is not a 9.5 like the 80 - so that won't work for you. Like I said not sure what the ratios are for the 78 or what size front punkin is on it innner axle spline count etc - that stuff matters when putting the diff in - that's why I say check out the part numbers in the EPC. If the 78 series inner axles are the same as the HZJ79 then you can fit the 80 series front diff.

All this is confusing stuff and I have learned the hard way when it comes to trying to fit stuff - my HZJ79 is all newly designed stuff - so just about everything from older cruisers doesn't fit it.

To make life easiest I would just do a complete axle/diff swap end for end with your 70 and then you are done with it. All you have to do is make some coil mounts - alot less time consuming than pulling diffs and finding out something doesn't fit. Just my opinion.
 
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