diff ratios with sas

[4x4 suzi]

Hi Guys trying to do some research and still learning, with doing a SAS do the diff ratios have to be same as standard if u are changing the rear diff, i have a nk 2.8 itd which i beleive has 4.9 diff ratio's so if u put gq diffs under it with 4.1's would this matter? i beleive this would make the gearing higher on road so you would have to change the centres anyway to get it back to standard or even further the other way to run bigger rubber? any info would be great

[v6triton]

hey mate, ive had the same thoughts, the conversion your after will set u back roughly 10k and onwards. your best option is to convert to 75series diffs or dana 35's but your problem is the transfer case, u will need an adaptor plate to mate up the new transfer case to your gearbox. the IFS transfer case will chew out the front input shaft bearing on your transfer case because the tailshaft is designed to spin in a straight line, thats why an ifs diff is solid mounted. add extra money for transfer case. best bet is to wind up ur torsion bars and fit bigger rubber or for the money ur willing to waste buy something thats got factory live axles. but then again, if ur triton is a 2.8 i beleive ur diff ratios are 5.29, v6's are 4.9 and 4cyl are 4.62, and im 80percent sure that these diff ratios are interchangable.

[4x4 suzi]

hey mate, you not sure at to do. does seem like alot of work and mostly money, its either that or put a arb locker in the front and maybe rear would be heaps cheaper, i just like the thought of the extra hight and strenght of axle/cvs u get with a solid axel.. and dont really wanna buy another forby as i have decked the paj out how i want it and have spent heaps of time doin it.. dual batterys, compressor and bullbar mounted tank. led lights allround for campin, bed in bak etc..

[arnijr]

This is not a minor modification. What you mostly gain with the sas is more articulation, the opportunity to have more lift plus some other smaller gains, such as strength, less snow accumulation in the front suspension and no cv-joint boots to replace. However, you are able to raise the Pajero enough to fit even 44 inch tires without a sas conversion, so unless you strongly feel you need it you might want to spend your money differently. Lockers in back and front will make a huge difference for less money for instance. A body lift and bigger tires will help and work on the suspension can certainly make a difference.

As for the diff ratios, you almost certainly have the 4.90. The 2.5D cars came with either 4.875 or 5.29 but these ratios are not interchangeable with the ratios in your diff, the 2.5TD diff is smaller. People have made it work with some custom machining but that's not a bolt in task. For the standard diffs in the 2.8TD there is no lower bolt in gearing available.

If you decide to go for a sas conversion, I'm assuming you'll be going for bigger tires. With bigger tires you want lower ratios (higher number). A 4.1 would be a bad choice, unless you were fitting a transfer case with lower gearing in both high and low ranges. Your transfer case is 1:1 in high and 1.90:1 in low. Some transfer cases have lower gearing in both high and low ranges, but unless you were putting one of those in you would want a lower diff ratio than you already have.

Now the 4.90 with the 1.90:1 transfer case will work with bigger tires. There are even trucks here on 44" tires running that combination. There are several other ways to lower your gearing should you need that:
- A transfer box from some Jeep Cherokees is pretty much the same super select box, but with lower gearing. If I recall correctly it's called NP242 and has a 2.42:1 ratio in low. This box can apparently be made to work with the super select system.
- You can fit crawler gears in your existing transfer case. A search on this site should help you with that, I don't have more info on those.
- It's possible to run two transfer cases, one that's been modified to only have the rear output that feeds into the second transfer case that has outputs to the front and rear diffs. That way you can select low on the first transfer case and 4llc on the second transfer case and get the combined down gearing. So if the first transfer case has a ratio of 2.0:1 and the second has a ratio of 2.5:1, selecting low on both of them gives you 5.0:1. This is not a trivial task and involves modifications to one transfer box, new mounts, shortening and lengthening of driveshafts and fabrication for the linkages.

[4x4 suzi]

Thanks heaps for all the info, yea still deciding at the moment its not my every day driver but shortly it may be and doing 900kms a week dont want to be running massive tyres so ill have to see.. might just go some lockers F+R.. any one else got info on wat they have down and how it works.. good or bad?

[alexiboris]

This is not a minor modification. What you mostly gain with the sas is more articulation, the opportunity to have more lift plus some other smaller gains, such as strength, less snow accumulation in the front suspension and no cv-joint boots to replace. However, you are able to raise the Pajero enough to fit even 44 inch tires without a sas conversion, so unless you strongly feel you need it you might want to spend your money differently. Lockers in back and front will make a huge difference for less money for instance. A body lift and bigger tires will help and work on the suspension can certainly make a difference.

As for the diff ratios, you almost certainly have the 4.90. The 2.5D cars came with either 4.875 or 5.29 but these ratios are not interchangeable with the ratios in your diff, the 2.5TD diff is smaller. People have made it work with some custom machining but that's not a bolt in task. For the standard diffs in the 2.8TD there is no lower bolt in gearing available.

If you decide to go for a sas conversion, I'm assuming you'll be going for bigger tires. With bigger tires you want lower ratios (higher number). A 4.1 would be a bad choice, unless you were fitting a transfer case with lower gearing in both high and low ranges. Your transfer case is 1:1 in high and 1.90:1 in low. Some transfer cases have lower gearing in both high and low ranges, but unless you were putting one of those in you would want a lower diff ratio than you already have.

Now the 4.90 with the 1.90:1 transfer case will work with bigger tires. There are even trucks here on 44" tires running that combination. There are several other ways to lower your gearing should you need that:
- A transfer box from some Jeep Cherokees is pretty much the same super select box, but with lower gearing. If I recall correctly it's called NP242 and has a 2.42:1 ratio in low. This box can apparently be made to work with the super select system.
- You can fit crawler gears in your existing transfer case. A search on this site should help you with that, I don't have more info on those.
- It's possible to run two transfer cases, one that's been modified to only have the rear output that feeds into the second transfer case that has outputs to the front and rear diffs. That way you can select low on the first transfer case and 4llc on the second transfer case and get the combined down gearing. So if the first transfer case has a ratio of 2.0:1 and the second has a ratio of 2.5:1, selecting low on both of them gives you 5.0:1. This is not a trivial task and involves modifications to one transfer box, new mounts, shortening and lengthening of driveshafts and fabrication for the linkages.

Any pics of Pajero's with 44" tyres?

[arnijr]

Any pics of Pajero's with 44" tyres?

Sure.

Here are a couple of pictures I took on top of a glacier, during a volcanic eruption. That's a bit of the outer limits, right? The black stuff you see on top of the snow is volcanic ash. If I recall correctly there's one 44" and two 38":





Also a couple other pictures taken the same day on top of the glacier. The 44" SAR Land Cruiser is our ride, with a mate standing by it.

[alexiboris]

Thanks for the pics. Amazing scenery!

[big wheel sigma]

My short paj has 2" body lift, 2" rear spring lift, wound up tortion bars, and cut bump stops, front locker (arb) 4.6 diff ratios, and run 35's on weekends, works well, actually works Aesome, will keep up and over take any patrol.$150 for rear springs and stock shocks so springs don't fall out, O and no rear sway bar, it will limit your rear travel alot.

[4x4 suzi]

how do you go with braking cv's and axels when your running 35's.. and just general strain on everything

[big wheel sigma]

I've broken more cv's on 33muddies than on my 35 silverstone extremes, plus it got 3.5L engine, g/box and larger diffs, I just use the locker and right foot less and trust the tyres more. The rear transfer output shaft is now showing signs and noises of wear, but the car has been Like this for about 7 yrs now withthe lift and tyres

[4x4 suzi]

oh ok, wonder y that is you would think they would be heavier and that.. wats your fuel consumption like on 35's

[big wheel sigma]

SHIT, but they only get used off-road