Q: BJ4 vs B44 diff gear and outdrive

[NSDie]

Quick question guys. The B44 diff set a direct fit for the BJ4 WE? (I know that they are from AE but just want to double confirm). I noticed that the B44 diff uses many more shims on the outdrive while the BJ4 only uses one on each side. Is the BJ4 WE transmission case a little bit narrower?

[jcb]

The B44 diff well the outdrives are different to the ones on the BJ4we. If I remember rightly the B44 outdrives are quite a bit shorter. As for the gears and internals I think these are the same.

I am not quite sure about the shims, I did my B44 diffs as per the instruction manual and now that it's been run it's lovely and free. I seem to remember putting a lot more shims on the BJ4 diff to make the mesh tighter so that I stopped shredding gears.

Hope that helps.

[NSDie]

Anyone here can confirm if the new associated outdrive is a little bit different in dimemsions? Just wanna get it right if I happen to replace the outdrive in the future with the new associated outdrive.....which is very soon.

[DaHomie]

Originally Posted by NSDie

Anyone here can confirm if the new associated outdrive is a little bit different in dimemsions? Just wanna get it right if I happen to replace the outdrive in the future with the new associated outdrive.....which is very soon.

I can confirm that the B44 Diff Outdrives are NOT different in terms of dimensions aka they are a perfect fit as such (and a little lighter than the NTC3 outdrives originally used in the BJ4WE by the way...) You will however make sure that you use the correct diff washers with the B44 outdrives, since the ones on the B44 are a different dimensions from a BJ4WE/NTC3.

So if you decide to get the B44 outdrives, make sure you also get the diff washers for the B44 and you will be just fine.

I run B44 diffs in my BJ4WE, works like a charm. Shim it a touch to the tight side when gears are brand new and it will free up and run brilliant after a few runs (just like the B44).

//DaHomie

[KBRacing]

How much little lighter are the B44 diffs, than the original NTC3 diff ... ???

[DaHomie]

Originally Posted by KBRacing

How much little lighter are the B44 diffs, than the original NTC3 diff ... ???

I honestly don't remembr the exact measurement.
The B44 outdrives are machined like the B4 lightweight outdrives and also the B44 diff washers is a larger inner diameter resulting in less total mass.
I weighed and compared the completed diff assemblies and all in all we are talking a few grams. Not much but less rotating mass is less rotating mass :-)

//DaHomie

[NSDie]

2 shims on each side (bJ4) vs 4 shims (B44) on one side and 3 shims on the other side, well... that's according to the manuals of B44 and BJ4 anyways. That's a lot of shimming and play we're talking about. I bet all the BJ4 owners must be shimming all their diffs after a few runs.......

[Lee]

Nope, i shimmed it when i built my first one and left it like that for a year until i built a new car.