i have 80s diffs with 42s powered by a v8 and reduction gears and no problems yet. i have longfield cvs, axles and drive flanges and locker to beef up the front end, so far only locker in rear.Bitsamissin wrote:If it were me I'd be going 80 Series front and rear with coils.
Bigger brakes, CV's, rear discs, wider track, full floater rear etc.
If you want outright strength then Nissan GU Patrol.
The lowest ratio you can get for the Nissan stuff is 4.88 but there are 5.29 and 5.7 ratio's for the Tojo stuff.
It's a very tall order to ask a 4 banger to turn 38's and most comp guys opt for an engine swap to turn rubber that big rather than try to compensate with gearing. The trouble with the Tojo stuff is that IMHO the C&P just aren't strong enough for above 35/36"s.
The combo you are proposing has been tried and tested resulting in numerous busted C&P's.
I had 3.0 V6 5sp with a front HP 8" Tojo diff and the Mitsi 9" rear with 5.29's ARB locker and treated CV's running 35"s (35.6") without any drama's but I always felt that was the limit of that combination. I did break the standard CV's but couldn't break the treated ones.
Some friends were running 36"s without issues on the same front axle combo as mine in their Tojo's so that is possible.
My problem was breaking the 28 spline rear axles.
The truck had good clearance and drove onroad ok I also had 2.85 t/case gears so 1st low range was 60:1 (not too bad).
There is also the question of ground clearance the larger diff you go the bigger the tyres you need to keep the clearance the same.
A Dana 44 is roughly the same size & strength of a Tojo 8" diff and axles so your going to break stuff running 38"s with a stock D44 of course you can upgrade from the numerous US aftermarket industries.
I know it's tough to decide as there are various permutations so good luck.
Your build looks good ill keep an eye on this one!!
Evan