4wd question

nairobery · Post by **nairobery** » Tue Apr 29, 2014 9:17 pm

Am just puzzled and looking for answers.

When i press the 4wd button and it shows its on 4wd mode,trying to corner the car it seems to lock up like something is preventing it from moving turn left or right , but on a straight path it moves just fine.

Whats all that about??

Silverbullet · Post by **Silverbullet** » Tue Apr 29, 2014 9:38 pm

It could do that if you engage 4WD on bitumen/asphalt roads, only engage 4WD on dirt roads or the axles will wind up.

t.ridden · Post by **t.ridden** » Tue Apr 29, 2014 9:55 pm

Its because we don't have a centre diff. The total rotation or the rear wheels combined must equal that of the front wheels combined. When cornering, especially tight cornering, the rear wheels follow a shorter path, causing an imbalance of rotation front to rear and "winding up" the driveline, as SB put it.

sublime · Post by **sublime** » Tue Apr 29, 2014 9:57 pm

It would help if you inform us of what model and year is your Subaru but from you have described (and Silverbullet has already detailed) you have a part-time 4wd Subaru. This means the transmission is locked when in 4wd and you will not be able to turn on hard surfaces such as bitumen. There needs to be some slip as you would have on dirt or heavy rain.

nairobery · Post by **nairobery** » Tue Apr 29, 2014 10:11 pm

Silverbullet wrote:It could do that if you engage 4WD on bitumen/asphalt roads, only engage 4WD on dirt roads or the axles will wind up.

Thanks guys, i now understand why it locks up like that, really thought there was something wrong with the rear diff or gearbox.

1989 L series High roof EA71, will post pics later.

RSR 555 · Post by **RSR 555** » Wed Apr 30, 2014 12:06 am

I'm sure you posted pics earlier but I only remembered your car when you mentioned L.Series with EA71.

As the guys have said, this model is only designed to use 4WD when on loose or wet surfaces. On dry and hard surfaces the gearbox will bind up. This can happen even when going straight if your tyres are not of equal size and wear.

Remember your 4WD is not AWD of the later models, your 4WD is better for offroading than the AWD but only 2WD when not offroad.

NachaLuva · Post by **NachaLuva** » Wed Apr 30, 2014 5:53 pm

^ What he said

Be careful engaging 4WD on bitumen as you risk snapping something

nairobery · Post by **nairobery** » Thu May 01, 2014 1:09 am

RSR 555 wrote:I'm sure you posted pics earlier but I only remembered your car when you mentioned L.Series with EA71.

As the guys have said, this model is only designed to use 4WD when on loose or wet surfaces. On dry and hard surfaces the gearbox will bind up. This can happen even when going straight if your tyres are not of equal size and wear.

Remember your 4WD is not AWD of the later models, your 4WD is better for offroading than the AWD but only 2WD when not offroad.

Thanks for that info, will be really careful when to engage the 4wd as i really dont wona mess the gearbox up.

I just thought what was wrong with my car when i engaged it and it just locked up and wouldn't turn...

Another question....

My gearbox has the 4WD button, and i just saw another at the junkyard with the high and low lever. So question is, does one with the high and low perform better than the one i currently have ?

nairobery · Post by **nairobery** » Thu May 01, 2014 1:11 am

NachaLuva wrote:^ What he said

Be careful engaging 4WD on bitumen as you risk snapping something

Thanks

Proton mouse · Post by **Proton mouse** » Thu May 01, 2014 8:36 am

nairobery wrote: My gearbox has the 4WD button, and i just saw another at the junkyard with the high and low lever. So question is, does one with the high and low perform better than the one i currently have ?

Would be much better for soft sand/mud/climbing things!
If you were to swap gearbox over, make sure your diff ratio is the same as the gearbox's, or transplant the matching diff with it. There will be a sticker on your diff, generally 3.7 or 3.9, the 3.9 is better again for 4wd work.

John

nairobery · Post by **nairobery** » Thu May 01, 2014 2:50 pm

Proton mouse wrote:Would be much better for soft sand/mud/climbing things!
If you were to swap gearbox over, make sure your diff ratio is the same as the gearbox's, or transplant the matching diff with it. There will be a sticker on your diff, generally 3.7 or 3.9, the 3.9 is better again for 4wd work.

John

Ok great, yeah i checked my diff and it says 3.9 , well i also have seen people here talk about the dual range so is the high and low lever a dual range or my current one is also a dual range?
Sorry too many questions

Thanks in advance

wagonist · Post by **wagonist** » Thu May 01, 2014 3:03 pm

If you're pushing a button to engage 4wd, then no, it's not dual range.
The 2nd lever has 3 positions (FWD, 4wd high, 4wd low) & makes your 4wd button redundant.

YouTube · Post by **El_Freddo** » Sat May 03, 2014 11:15 am

If you're looking at lifting and increasing the tyre diametre, I'd definitely grab the dual range gearbox (and the rear diff if it's different to your ratio now).

Cheers

Bennie

RSR 555 · Post by **RSR 555** » Tue May 06, 2014 11:12 am

In Aus, the 1985-86 model came with the push button single range 4WD gearbox and the 1987 onwards came with Dual Range. If you wish to swap to D/R, you'll need to replace the gearbox, gear shifter and interior console pieces. There is also some small wiring changes which may include dash cluster mod for a low range light (only if you want it?)

nairobery · Post by **nairobery** » Wed May 07, 2014 1:12 am

RSR 555 wrote:In Aus, the 1985-86 model came with the push button single range 4WD gearbox and the 1987 onwards came with Dual Range. If you wish to swap to D/R, you'll need to replace the gearbox, gear shifter and interior console pieces. There is also some small wiring changes which may include dash cluster mod for a low range light (only if you want it?)

Yes i have to replace all that and lucky i saw all of them at the yard.Thanks

nairobery · Post by **nairobery** » Wed May 07, 2014 1:14 am

RSR 555 wrote:I'm sure you posted pics earlier but I only remembered your car when you mentioned L.Series with EA71.

As the guys have said, this model is only designed to use 4WD when on loose or wet surfaces. On dry and hard surfaces the gearbox will bind up. This can happen even when going straight if your tyres are not of equal size and wear.

Remember your 4WD is not AWD of the later models, your 4WD is better for offroading than the AWD but only 2WD when not offroad.

So does putting an LSD rear diff eliminate the lock up even on dry and hard surfaces ??

nairobery · Post by **nairobery** » Wed May 07, 2014 1:15 am

El_Freddo wrote:If you're looking at lifting and increasing the tyre diametre, I'd definitely grab the dual range gearbox (and the rear diff if it's different to your ratio now).

Cheers

Bennie

Am on 13 inch right now thinking of replacing with 14 inch so i guess am on the right track by getting the dual range

t.ridden · Post by **t.ridden** » Wed May 07, 2014 11:49 am

nairobery wrote:So does putting an LSD rear diff eliminate the lock up even on dry and hard surfaces ??

Short answer, no, it won't. The AWDs have a center diff that splits the drive front:rear. The Part Time 4WD doesnt have a center diff and this is what causes the binding. if the rear wheels spin at a different total rate to the fronts, there's no slip to make up for it

However, if you can get your hands on an LSD rear, go for it, its a huge improvement offroad. not as good as a lockable diff but its the best we can do with a Subaru

NachaLuva · Post by **NachaLuva** » Wed May 07, 2014 5:05 pm

What he said

RSR 555 · Post by **RSR 555** » Wed May 07, 2014 11:21 pm

nairobery wrote:Yes i have to replace all that and lucky i saw all of them at the yard.Thanks

That's great to hear and we want pics of your progress

nairobery wrote:So does putting an LSD rear diff eliminate the lock up even on dry and hard surfaces ??

Nope, the binding comes from the tail shaft turning at a different speed to the gearbox. The LSD just allows better drive to both rear wheels, so it would more than likely make it worse. I wouldn't worry about the LSD unless you're planning to do lots of off roading.

nairobery wrote:Am on 13 inch right now thinking of replacing with 14 inch so i guess am on the right track by getting the dual range

I'd also recommend 3.9 ratio final drive if you're going 14" wheels