1981 fj45 front diff rebuild

[tops]

Hi all, I was up at double island point last weekend when the front drive-shaft fell off! It's only the second trip since buying the 45 a couple of weeks ago. It looks like the teeth on the uni are gone and its very loose (suggesting internal diff is cactus). I'm now tossing up between rebuilding the front diff or replacing with 40/60 series disc brake (its currently drums all round). Unfortunately, my budget doesn't stretch to 80 diffs front and rear...

What can people suggest? Any useful experience/tips would be welcomed.

Thanks,

tops (newbie)
black 81 fj45 pretty much stocko...

[pig in shit]

if you have the money then yeah i would say definately go the new diff with discs

[loosecanon]

hey mate sorry to hear about your truck.
but on a good note if your in briz i have a spare disc brake diff that ill sell to ya, well i don't need 2, it's not advertised anywhere as i figure it'd be good to help out someone like you who needs it asap, no axle's or centre in it, if your interested call on 0423366002,

cheers
loooosecanon

[RAY185]

I'm confused. Your front prop shaft fell out? The teeth on the uni are gone? Something is loose suggesting internal diff is cactus? You got any pics of this stuff.

Normal to have a bit of freeplay in the front diff. Why did the tailshaft fall out, too short?

[shorty_f0rty]

is this the same 45 that scotto was telling me about today?

I might be able to help out with a disk front end and another center..

ray i think from what scotto was telling me the pinion unwound or came loose or something.. not 100% sure..

[tops]

is this the same 45 that scotto was telling me about today?

I might be able to help out with a disk front end and another center..

ray i think from what scotto was telling me the pinion unwound or came loose or something.. not 100% sure..

Yep, same truck. I'll try and figure out how to post some pics now. The driveshaft simply clunked and dropped into the sand. There was a fairly bad grinding sound which started when we left camp in the morning. I shifted back into 2x4 and it stopped (thinking transfer case at this point). We hit some soft stuff and stopped to engage 4x4. The grinding came back but she went forward so we kept on. Then the clunk and car stopped. Underneath the shaft was facefirst in the sand, flange still attached (it sheared off at the uni). The spline from the uni was sitting out and had a small amount of play (nothing unusual though).

I dropped the shaft and went home. Scotto and I pulled it to bits and found the thread on the pinion nut stripped. A new pinion nut would not take either as the uni has been stripped. That's about where we are now.

Thanks for the replies so far. I may take up the offer for the diff depending on how much a new centre is going to cost. I'm thinking a new centre in my diff for now until budget allows for a more serious suspension overhaul. See how we go. Cheers.

[tops]

[scotto]

Gday dudes yeah this is the one I mentioned.
Good to see ya in here Trev some top dudes to help out..

Basically looks like the PO mighta got a little short term memory disfunction and forgot to notch the nut once done up
Unlucky eh..

Pinion is threaded bad enough we couldn't get a nut on (old or new) to tighten it right up and see what sort of shape the front centre is in.
It's been floating around a bit, in my book = pull it out for a look.
Does anyone have the technology to re-thread a pinion??
Could then drive it, have a listen, check the oil etc..
The splines in the flange are showing signs of slippage too, prob from where things have been freestyling.

So Tops I reckon work out the budget and suss out the cost on a disk front end. Reckon it might be worth double checking the rear too.

scotto


Failing that it's a toss up between a replacement front centre or have the one you have checked out..

[RAY185]

Bugger. Yeah I would agree the pinion nut has come loose. Pretty sure it happened to Twisty but he caught it pretty early before any damage was done. Depending on how long its been loose that pinion is likely to be rooted but worth pulling the centre for a look. Either second hand centre (I have a spare 60 front diff if you need it - exactly the same as the 40) or as suggested a complete disc front housing is probably the best option if in the budget.

[tops]

thanks guys. Looks like I'll save for a complete disc front-end after considering the work/cost vs reward argument. Anyone have a 40 disc brake complete diff? Please let me know what you want for it. Thanks. Scotto, let me know when ur up next and if ya up to joining me and 24 of me closest mates (read rumbos) to help get the old girl walking on all fours again.

Another quick question....I'm pretty sure she's standard height (though haven't found one to compare yet)...would 33's get under there without needing lift? Figure someone's done this to a 45 at some stage and would know...cheers.

[TWISTY]

Yep, same thing happened to me on the way up to Double Island....Was doing 100km/hr on the motorway, and a mate driving behind me got on the uhf and said his truck is getting covered in oil, mine must be leaking somewhere.

Pulled over and seen this.


So lucky it didn't come all the way off at those speeds! Only cause I could see is when the airlocker was installed they didn't knock the tabs in on the nut (as described above). Anyway, thread was damaged pretty bad on the pinion, but with help from a mate, we took to it with a thread file, and got a new nut back on with plenty of locktight, and smashed the notches in on the nut. Has held for about 3 more trips since.

[tops]

Well, finally the 45 has had a driveline rebuild. Happy to report new steering, LSD rear, new swivel hubs, etc. Unhappy to report ignition problem If you guys know anything about 2f auto electrics, please see my other post. Cheers.

[keencdk]

I have at least on, and I think 2 diff centres lying around which we OK when pulled, though coming from a 40 I couldn't tell if they were noisy etc as the cars are so noisy. Anyways, you can have one for a carton of beer. I am at Albany Creek