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4.10 and 4.11 diff centres

Posted: Thu Jan 17, 2008 3:53 pm
by V8 Rangie
Ok here's the go before I start going nuts!

The other day I fitted the LC 4.1 rear diff on my rangie. Have a GQ 4.11 in front. Drove great :-) put the centre diff lock in and drove about 20 meters to discover bad vibration. Took the centre diff lock out and all fine.

The rear is a 4.10 ---- 41-10
The front is a 4.1----37-9

Your reckon this is the prob? I always assumed that there would be no noticable difference .

I am thinking I have to get a 37-9 toyo centre for the rear.

Please can anyone shed some light on this subject

PS. I jacked up the car and with x4 turns of the tyres, they were about 4inches different

Cheers

Cameron

Posted: Thu Jan 17, 2008 6:38 pm
by cloughy
No .0:1 wont make a lick of difference

Beat your GQ diff is a 3.9:1 or a 4.3:1 :D

Posted: Fri Jan 18, 2008 8:06 am
by V8 Rangie
yeah I know...

The front GQ had a 3.9 in it and I put a 4.11 (37:9) centre in 2 weeks ago to suit the LC rear diff

Its got me beat :roll:

Posted: Fri Jan 18, 2008 8:43 am
by cloughy
So they're both DEFINATELY that ratio??? as in counted the teeth 100%??

If so, maybe cactus centre diff???

Posted: Fri Jan 18, 2008 8:53 am
by V8 Rangie
Thanks for the reply cloughy

Can't be any more sure.. I even counted the number of teeth and compared to what it says on the crown wheel on the GQ before I put the centre in.

Centre diff was working perfect before I put the rear LC in.. but never put centre lock in on the road though. Locks and unlocks fine.

Do you think it might have a stuffed gear in the centre diff?

I rang Diff Lapping in brissy yesterday and they reckon 4.11 to 4.10 would cause that specially running larger tyres.. but then again who's to believe as they wanna fit a 37:9 gears in my LC diff to make them the same ($550)

Argh this is so frustrating!

Camo

Posted: Fri Jan 18, 2008 8:58 am
by cloughy
V8 Rangie wrote:Thanks for the reply cloughy

Can't be any more sure.. I even counted the number of teeth and compared to what it says on the crown wheel on the GQ before I put the centre in.

Centre diff was working perfect before I put the rear LC in.. but never put centre lock in on the road though. Locks and unlocks fine.

Do you think it might have a stuffed gear in the centre diff?

I rang Diff Lapping in brissy yesterday and they reckon 4.11 to 4.10 would cause that specially running larger tyres.. but then again who's to believe as they wanna fit a 37:9 gears in my LC diff to make them the same ($550)

Argh this is so frustrating!

Camo
I had 3.54:1 and 3.5:1 9" at one stage, was with a nissan transfer case at the time, but never anything wierd in 4wd

No reason for your centre diff to be cactoid now if it wasn't before, but you saying this only happens centre diff locked?, I'd be dropping tailshafts and going for a drive

Posted: Fri Jan 18, 2008 9:18 am
by V8 Rangie
I know I did that :cry:

When I fitted the LC rear I took front propshaft out (had 3.9 in front) and drove with centre transfer locked.. rear diff went perfect . took it to 120k's and no vibration :)

Put front 4.11 in front that afternoon.. drove it and was nice

then put transfer in lock and lasted about 20 meters before things started shaking :?

Hrmmm

Posted: Fri Jan 18, 2008 9:52 am
by cloughy
V8 Rangie wrote:I know I did that :cry:

When I fitted the LC rear I took front propshaft out (had 3.9 in front) and drove with centre transfer locked.. rear diff went perfect . took it to 120k's and no vibration :)

Put front 4.11 in front that afternoon.. drove it and was nice

then put transfer in lock and lasted about 20 meters before things started shaking :?

Hrmmm
Strange days indeed....... :?

Posted: Fri Jan 18, 2008 10:13 am
by V8 Rangie
Thats it..

I'm totally out of ideas

trial and errors are starting to get expensive

anyone got a pair of rover diffs they wanna sell me cheap :roll:

Posted: Fri Jan 18, 2008 10:38 am
by outlaw
go back to maxi enhanced rover diffs :finger:

Posted: Fri Jan 18, 2008 10:46 am
by V8 Rangie
Yep cheers knob

Posted: Fri Jan 18, 2008 11:44 am
by GRIMACE
V8 Rangie wrote:Yep cheers knob
I have standard 10spline diffs for sale :lol: cheap for you - only $500 :D

Posted: Fri Jan 18, 2008 12:03 pm
by V8 Rangie
woohoo! 10 spline! haha

I will pull both diff centres out and take em into a diff place and see what they reckon

dunno what else to do!

Posted: Fri Jan 18, 2008 12:21 pm
by Slunnie
snot the tailshaft or its mounting is it?

Posted: Fri Jan 18, 2008 12:31 pm
by V8 Rangie
Nah nothing to do with that.. did it when I put the centre diff lock in

Rang another diff place here on the gold coast and they reckon its the difference between 4.11 and 4.10.. they were very sure

found out a 75 series 4.11 will go straight into the 80 series housing

looks like this may be the way to go

Camo

Posted: Fri Jan 18, 2008 1:03 pm
by lokka
Slunnie wrote:snot the tailshaft or its mounting is it?
Yep thats were id be lookin if the flanges for the unis arnt right it would vibrate ...

The difference between the raitos shouldent be ya problem weres the vibs coming from ??? may even be the unis on the shafts being out of phase or not mounted up right ....

Sounds verry strange tho best of luck with it

Posted: Fri Jan 18, 2008 1:52 pm
by V8 Rangie
Can't be uni's as it drives perfect without centre diff lock in

only when I put the centre diff lock in it starts to shake after about 20-30 meters

starting to think it may need a 4.11 rear centre

Camo

http://www.outerlimits4x4.com/phpBB2/viewtopic.php?t=130440&

Posted: Sat Jan 19, 2008 1:01 pm
by swamp
try locking the centre diff and driving on a gravel surface, if it doesn't vibrate I would think it was the difference in ratios.

Posted: Sat Jan 19, 2008 1:58 pm
by V8 Rangie
Hi Swamp

Nah it didn't shake at all on a gravel (crusher dust) road

I'm sure it would prolly be fine to drive on road but would eventually wreck my transfer from wind-up.

Spose will just find a 4.11 (37-9) rear diff centre .. from ringing around it appears that 60, 75 series centre will go straight in! would be good :-)

Cam

Posted: Sat Jan 19, 2008 1:59 pm
by bigbad
on a 35 tyre the difference is about 4 driveshaft revolutions per kilometre

Posted: Sun Jan 20, 2008 8:16 pm
by Slunnie
There would no doubt be more difference from uneven tyre wear.

Posted: Mon Jan 21, 2008 10:34 am
by V8 Rangie
Has new tyres on it

only way to know for sure is to put 4.11 in rear

think i have found a 60 series centre with an ARB locker in it :-)

apparently it will go in an 80 series housing

at least i know my ratios are the same .. both 37:9's... 4.11

Has to fix it!

Camo

Posted: Mon Jan 21, 2008 3:10 pm
by Reddo
...see what happens when you mess with mother nature:)

...but seriously, I reckon it is the ratio difference causing wind up and release....

Posted: Mon Jan 21, 2008 4:10 pm
by crankycruiser
V8 Rangie wrote:Has new tyres on it

only way to know for sure is to put 4.11 in rear

think i have found a 60 series centre with an ARB locker in it :-)

apparently it will go in an 80 series housing

at least i know my ratios are the same .. both 37:9's... 4.11

Has to fix it!

Camo
Is it an 80 centre in it now?? as they are 4.11

Posted: Mon Jan 21, 2008 4:24 pm
by V8 Rangie
Nah mate.. thats what I got told when I bought the diff

argh

80 series are 4.10 (41:10)

older than 1990 eg 60 series are 4.11 (37:9)

Posted: Mon Jan 21, 2008 4:34 pm
by crankycruiser
Yep your dead right mate...!
Just went out to the shed and counted the teeth on my old rear diff

My Bad!!!

I was always under the impression they were 4.11's.. Learn something new every day :lol:

Posted: Mon Jan 21, 2008 4:38 pm
by V8 Rangie
haha too funny

I'm just hoping the 60 series will fit in the 80 series housing

Ive been told by a few that it will.. spose will take a punt as I'm about to get one sent up from Sydney with an ARB locker in it :-)

ah the joys of modifications...

Posted: Mon Jan 21, 2008 4:45 pm
by crankycruiser
V8 Rangie wrote:haha too funny

I'm just hoping the 60 series will fit in the 80 series housing

Ive been told by a few that it will.. spose will take a punt as I'm about to get one sent up from Sydney with an ARB locker in it :-)

ah the joys of modifications...
I'm pretty sure they do fit...........


but the last thing i told ya was full of crap lol

Posted: Mon Jan 21, 2008 6:06 pm
by GRIMACE
they fit ;)

Posted: Mon Jan 21, 2008 7:25 pm
by V8 Rangie
Thanks for that AnthonyP from Iraq and Cranky Cruiser from Tassie :lol:

I feel alot better now and am sure the centre will fit :roll:

Hope its all :armsup: