[cbzook]

i am currently running 30's on my zook. i am lookin at changing the diff ratios so i can go bigger tyres, but i have no idea who makes them for suzuki. so if anyone know where to get them from could u please let me know. thanks

[Bruce]

I assume you mean a Sierra?
Have you thought about a set of T/case gears. Calmini have a nice set that reduce gearing by 127%. Could run 31's (as we do) without a worry at all. Normal driving with 30,31's is fine but put it into low and you have 127% reduction making it great for offroad.

[Damo]

To add to what Bruce said, diff gears can be sourced from Vitara front diffs. ~5.1:1 and ~4.5:1 are available, though I believe the latter are more difficult to come by.

Most people go for the transfer gears as they give better reduction in low range, but Joe in Melbourne has had good experience running the diff gears.

Setting up diffs isn't as straight forward as putting gears in a transfer case, so that may be a factor for you too. But I think ultimately the terrain you drive is going to be the biggest factor.

[oscar]

don't bother with vit diffs cuz they don't last and shit on road cuz ya ratio is changed.

[basketcase]

http://lowrangeoffroad.com/

Have look on there. Good price and sevice. Most brands available.

[joeblow]

oscar wrote:

don't bother with vit diffs cuz they don't last and shit on road cuz ya ratio is changed.

WTF?

we've been running diff gears for ages ( about 15 vehicles just in our group) and have never had any dramas. they also gear your vehicle correctly depending on tyres. we have found (and yes we have used them) t/case gears causr too many headaches, eg-noise, t/case mounts failing, extra stresses on tailshafts and unis. i've got twin transfers but find 99% of the time the gears are too low for what i need, so i just use standard lowrange with diff gears. speak to a driveline engineer (i'm lucky enough to work with some of the best in the country) and they will show you the maths on driveline stresses and torque and will say the most reliable way is go diff gears. these are my opinions only, as over the years all i've had to do is fit diff centres and not chase my tail fixing broken shit. i'm not telling you what to buy also, that is your choice, but as a rule in my workshop i won't fit lockrights or t/case gears because i don't want the eventuall headaches comming my way. like i said these are my opinions only, so think about it, do your research, and make your own choice.

[oscar]

i guess diff ppl have diff expieriences than ah!

[jkzuki]

For years, I have had people tell me how unreliable s3 rockhoppers are. Have not had a prob with em in over 5 years!

[Damo]

joeblow wrote:

oscar wrote:

don't bother with vit diffs cuz they don't last and shit on road cuz ya ratio is changed.

WTF?

we've been running diff gears for ages ( about 15 vehicles just in our group) and have never had any dramas. they also gear your vehicle correctly depending on tyres. we have found (and yes we have used them) t/case gears causr too many headaches, eg-noise, t/case mounts failing, extra stresses on tailshafts and unis. i've got twin transfers but find 99% of the time the gears are too low for what i need, so i just use standard lowrange with diff gears. speak to a driveline engineer (i'm lucky enough to work with some of the best in the country) and they will show you the maths on driveline stresses and torque and will say the most reliable way is go diff gears. these are my opinions only, as over the years all i've had to do is fit diff centres and not chase my tail fixing broken shit. i'm not telling you what to buy also, that is your choice, but as a rule in my workshop i won't fit lockrights or t/case gears because i don't want the eventuall headaches comming my way. like i said these are my opinions only, so think about it, do your research, and make your own choice.

Just out of interest Joe, do you think the results you have been having would be the same regardless of the terrain you're driving?

[joeblow]

don't think so, my vehicle and others have either been driven or shipped to various places and or terrains. and i would have to say the best, grippiest( if thats a word) rock shit you can get is that lovely stuff found in tassie. like i said its my opinion and i know others won't agree, it just stems from having to wheel and work on vehicles that have all sorts of gearing mods done to them, and at the end of the day we have decided on diff gears, but that is us, and a lot of our group have had both. once again its only my opinion, i like setting up a reliable truck and that will include all components, the one thing that has never come back to bite me in the arse has been diff gears. i'm not only talking about breakages but also quietness and other things like having to beef up mounts and tailshafts. at the end of the day i have found using factory parts, though arranged in many wacky forms, has been very reliable for us, and we all run more horespower, 33's and all have airlockers. like i said, i like improving cars, not fixing them.

[esky]

oscar wrote:

i guess diff ppl have diff expieriences than ah!

And transfer people have transfer experiences. ah ha ha ha ha.

[oscar]

funny bastard arn't ya! haha

[Damo]

joeblow wrote:

don't think so, my vehicle and others have either been driven or shipped to various places and or terrains. and i would have to say the best, grippiest( if thats a word) rock shit you can get is that lovely stuff found in tassie. like i said its my opinion and i know others won't agree, it just stems from having to wheel and work on vehicles that have all sorts of gearing mods done to them, and at the end of the day we have decided on diff gears, but that is us, and a lot of our group have had both. once again its only my opinion, i like setting up a reliable truck and that will include all components, the one thing that has never come back to bite me in the arse has been diff gears. i'm not only talking about breakages but also quietness and other things like having to beef up mounts and tailshafts. at the end of the day i have found using factory parts, though arranged in many wacky forms, has been very reliable for us, and we all run more horespower, 33's and all have airlockers. like i said, i like improving cars, not fixing them.

The thing that always made me nervous about the 5.1 diff gears is the fact the pinion has to be so much smaller, and the subsequent assumption is that surely this would effect it's strength and therefor reliability. The fact that your experience shows this not to be a problem is very interesting.

[joeblow]

damn goog point damo. yes, the pinion is smaller, but the driveline and axles now require a lot less torque to rotate them. forces are actually alot less on a 5.1 pinion than say the forces on a 3.7 diff with t/case gears. but i wouldn't use these gears on anything larger than 33's. and like i said i base my experiences on having dealt with both systems. other factors come into play like who set the diff up etc, but if its done correctly it should last forever, and thats another reason i won't use lockrights, cause they won't make other parts last forever.

[just_cruizin]

Is the crown wheel on the 5.1 larger diameter? I'm just trying to think the process backwards. torque required by the tyres will remain unchanged regardless for a certain speed, it tracks back to the engines capability to delivery the required torque at the required rpm. Gears just allow the engine to rev higher thus providing the required torque with the same wheel speed. Final loading is provided by the resistance ie traction, not by the engine.

[Damo]

just_cruizin wrote:

Is the crown wheel on the 5.1 larger diameter? I'm just trying to think the process backwards. torque required by the tyres will remain unchanged regardless for a certain speed, it tracks back to the engines capability to delivery the required torque at the required rpm. Gears just allow the engine to rev higher thus providing the required torque with the same wheel speed. Final loading is provided by the resistance ie traction, not by the engine.

Everything else being equal the change to 5.1:1 diff gears would give more mechanical advantage to the engine compared to the 3.7:1 gears. Think of it in terms of leverage, the 5.1:1 gears are the equivelent of extending your breaker bar with a length of pipe. Sorry, but I have to put it in "Damo can understand" terms

[royce]

the closer you have your reduction the less load everything between it and the power source will see, thats why portals are strong

so when you have big reduction in the transfer then a lot more load is placed on the mounts and tailshaft