Thread: Front & Rear diffs must match!

My 2A is back on the road after a 3 month stint of repairs and swearing. I had swapped out a complete front hub to hub from a donor 2A I bought a while ago along with a set of parabolics, new shocks etc (details to come in a more involved thread).
When testing my new articulation on car ramps I popped the rear diff. So replaced with a spare I had on hand.(not checking either ratio)
This weekend we went to Nth Straddie camping and it felt so bloody odd and lacked torque no matter how much juice I gave it. I soon figured out I was running different ratio diffs!
The donor was a 2A with a ford 250 crossflow and a C4 auto conversion, these are geared low and often are paired with an O/D or 3.54 ratio diffs.
Well, I have come to conclude I have a front running 3.54 and a rear with 4.7.
Even though I was on sand and the back end kept skipping I still built up enough wind up to prevent the transfer case from unlocking from Low range to 2WD (If you have free wheeling hubs it helps and I have 1 still as I ran out of time before camping to change the other to the fixed hub).
Apart from the very soft sand I ran in 2 wheel drive for the rest of the weekend and had no issues and the paras softened the ride slightly.
I now will change over to the 3.54 rear and see how I go with torque and 4WDing. I have a 186 so the ratio could be a bonus.
Over all, you can get by on two different ratio diffs if the ground is loose, but the ride it jumpy and the stress of blowing something important is not fun. All considered the weekend went well and the the weather was great.

The 186 does seem to lack torque, i'm thinking of getting a torque/tow cam and hoping it will be better. Those LR 4cyl are good for low down torque, but I'll try to work with what I have.

Originally Posted by Johnno1969

If the vehicle's got a 186 in it, I would imagine that 3.54 diffs would not exactly be to your advantage offroad. I thought the 186 motor in my Landy went alright until I drove Landies with Land Rover 4 cyl motors and realised how much low-down torque I was missing with the Holden engine - and that was with 4.7 diffs.