Whats the difference in low and high ratio diffs

[fester]

Hey guys what is the difference (other than the ratio itself) in low and high ratio diffs eg 3.55 and 3.73. I see them generally listed as seperate items for parts eg air lockers. Is it that the crownwheels are different thicknesses or something.

I ask because I'm chasing a price off soemone for a pair of Quadradrive diffs to toss up whether it's worth putting them in my CRD but trouble is they are from a V8 so I would have to be able to regear with my ratios. I don't really know whether it is possible or how due to the part differences for thing slike lockers etc.

Can anyone shed any light on whether it can be done EASILY???

[turbomart]

There is generally two different size carrier housings that the ring gear bolts to , lower ratios require a bigger diameter ring gear with more teeth.There is a break or point when you have to go to the bigger housing.

I would of thought the lower 3.73:1 ratio V8 diffs would be better if you wish to go bigger tyres.
Also their is more to it than a simple swap, The front ring gear requires the bearing to come off to remove the ring & this needs a special puller or destroy the bearing.
Both ends will need to be set up properly or they will be noisey , this is especially important if swapping ratios .

[fester]

There is generally two different size carrier housings that the ring gear bolts to , lower ratios require a bigger diameter ring gear with more teeth.There is a break or point when you have to go to the bigger housing.

I would of thought the lower 3.73:1 ratio V8 diffs would be better if you wish to go bigger tyres.
Also their is more to it than a simple swap, The front ring gear requires the bearing to come off to remove the ring & this needs a special puller or destroy the bearing.
Both ends will need to be set up properly or they will be noisey , this is especially important if swapping ratios .

Bugger was afraid of thaat, was hoping it was more llike the Japs which seem to be able to have any ratio on the one carrier.

Can't change the gearing it upsets the Merc gearbox and I have not found anything on the net that solves that issue. The box can handle bigger tyres but not axle ratios as it upsets the balance between axle speed sensors and gearbox output shaft sensor. Same problem I have with fitting a Lokka hence thinking outside the box a little instead of going the TracLoc and then maybe front air locker. Was thinking Quadradrive diff swap may end up cheaper seeing as a TracLoc has to be set up anyway but of course CRD Quadradrive diffs are very rare second hand.

[Chumby]

"but of course CRD Quadradrive diffs are very rare second hand"

Looked for a couple of years... found one owner... never found a secondhand one... very hard work...

Cheers
Chumby

[fester]

"but of course CRD Quadradrive diffs are very rare second hand"

Looked for a couple of years... found one owner... never found a secondhand one... very hard work...

Cheers
Chumby

Course this would not be an issue if the bloody Merc gearbox was not too smart for its own good. Found a Sth African dude asking the question about ratio changes on the US forums back in 2009 without a solution. That's how I found out a ratio change is out unless you can get the box reprogrammed and there was conjecture as to whether Jeep could do that or MB could do it or even if the dealers had access at all to do that.

Wouldn't be an issue at all if we could use the damn Lokka in a CRD.

Chumby would you mind PM'ing me what the set up of your TracLoc ended up costing you or here if you like. Other issue is whether I can get someone local to do it, otherwise I have an hour or 2 drive and piossibly have to leave ghe vehicle to get it done. I hate Salisbury style diffs for that reason, banjos are so much easier.