Holden202T wrote:the crewman is 1680mm or close enough to it, I have not 100% confirmed axle length difference but someone on here said it was about 50mm longer so assuming that I do get a 2inch longer outcome it means the crewman lengthened will end up about 1730mm .... which if anything I want wider cause the commodore wheels have more back space offset compared to the Bedford....
Hi 202t I ended up putting the correct measurements back on page 19. Was a bit out with the 50mm as it ended up being 95mm difference.
Cheers.
Holden202T wrote:to be honest I don't really know the details .... but crewman diffs are normally listed on ebay and such as M86 and 30 spline ?
Don't quote me on this but I think the number at the end is crown wheel size so a m75 is a 7.5" crown wheel and a m78 is 7.8" and yours must be a 8.6", bullet proof with 30 spline axles for your combination! Are they expensive and hard to find ?
I've heard a few horror stories about those M86 diffs. Noisy and tends to eat pinion bearings or the like. I hear it has something to do with the housing angle when mounted which apparently means the pinion bearings don't get lubricated properly. Seems odd though when you look at where the pinion is located in relation to the crown wheel.
yeah I read the same on another forum about the crown wheel sizes! .. this one cost me $550 with tailshaft .... but a lot of the LSD ones are around $1000.
if its just pinion angle that's the issue it wont be anymore
I do plan to renew all the bearings and such, but from first inspections, oil looked good and the teeth look good, also the bashlash is next to nothing so certainly not in bad condition.
No matter what the question is, the answer is always more horsepower!
ok so it looks like the axles are 95mm difference so that's going to mean my calcs are 45mm out .... meaning approx. 22.5mm wider on each side to what I had planned .... I can maybe reduce the 45mm by about 15mm by shortening the un-needed spline but im not sure I am going to need to.... I need to find out what max track increase I can do but otherwise I think it will work ok
im going to bolt up the crewman diff as it is now and dummy it up with the extra length added in and see where the wheels sit in the guards to be sure....
I've also got some research to do, because I've read that these diffs are 30 spline and larger crown wheel etc ... but these axles while they have a larger bearing and shaft, they are 28 spline Identical to the earlier commodores! I want to check the centre too, and see if it is in fact larger than the vn-vs unit ... im beginning to wonder if the v6 crewmans have different diffs to the V8's.
No matter what the question is, the answer is always more horsepower!
I have been struggling to find any information on the Crewman and One Tonner diffs. I have got one to rebuild as well.
Attached is all I have been able to find so far but it may be of some use.
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yeah I have been trawling google for info, and as yet I have not found a lot, I pulled my backing plate off last night and had a good look at the crown wheel, its most definitely a M78 not an M86 ..... so I am now wondering if V8's have the M86 ..... or if anything at all has them ? but theres certainly plenty of references on the net for crewmans with M86's.
my crown wheel is stamped with 0578 and 3.08 ..... the axles are 28 spline and the centre looks identical to the earlier commodore diffs I've played with.
so this is not an issue, but if there are in fact different diffs I just need to make sure I get the right axle to suit my centre!
as far as rebuilding it, if its a M78 then I'd say anything in books from VN-VS will apply for torque settings and lash/preload settings I'd say.
I also had some time last night to dummy up the crewman diff in the Bedford, I set it up so its where I want it on one side with the other side being 95mm too short, (to account for the lengthening) and the wheels should work out ok, just sitting inside the guards!
so I now need to start sourcing the rest of the pieces I need so I can start cutting and shutting!
No matter what the question is, the answer is always more horsepower!
