Talk to me about 4WD

[Stanky]

Evening,

 

I have been lusting over a Subaru Legacy 2.5 GX on auto-raider, and in the course of my research it has been suggested that the 4WD system can 'play up' though the guide is no more specific...

 

Now, as a lifelong 2wd kinda guy, this fills me with a bit of trepidation. If I was going to see one of these, or any 4wd vehicle for that matter, how would I know if the 3rd and 4th driven wheels were broken? All I can think of doing is getting someone to stand outside and me flooring it to see which wheels (if any) spin. there must be a better way than this?

 

I am aware that on things like Freelanders, the rear (?) prop can be removed to make it FWD only if the rear diff breaks/plays up/whatever, is this common across all 4wd vehicles or specific to OVROAD vehicles?

 

Info gratefully received from anyone in the know, or anyone who has been on the receiving end of information expedited by inebriated people in public houses.Info especially gratefully received if directly relevant to Subaru Legacy saloons of 1998 - 2003 vintage, which is currently tempting my overdraft towards previously unexplored depths.

 

Thanks

[steve_earwig]

I did some brief 4X4 investigations before I made the "they're all shit, pick one at random" choice of the yoyo. Removing the propshaft is specific to the Flealander, something to do with the centre diff but I was too busy laughing at all the other faults they have to remember what it was specifically. Volvos have some sort of 4WD when you need it system, it usually corrodes to death over the summer months and fails expensively the first time it snows.

 

I suspect that Subaru have been making 4WD systems long enough for them to know what they're doing, I'd have thought all the emissions gubbins will be what sucks your wallet dry. Advice wot I have been given by the guy that keeps having to fix the yoyo's is don't touch anything Japanese after about 1998-9, seems fair to me.

[dave21478]

I cant speak for Subarus, but the problem arises with many cars that are permanant 4wd, or AWD as its sometimes called.

You need some method of allowing for a speed difference between front and rear axles. Discos and Rangies have a centre differential, which can be locked. Many AWD cars like the Freelander have a viscous coupling  unit instead. The problem is that a VCU has a finite life as it depends on a silicone oil that gets thicker under shear loading. This deteriorates over time and can become less effective. Another problem is tyre changes. Most manufacturers will specify a maximum difference between front and rear tyre diameters, which is often just a few millimeters. If this difference is too large, the ratios of front and rear axles will be a little bit different and the VCU will have to slip more than its designed to in order to compensate.

In the freelander case, the VCU stiffens up until it wont slip in normal use which puts massive strain on the rest of the drivetrain and something will eventually brake. In the freelanders case, the next weakest point is the transfer box which is also the most expensive part.

As such, you ideally need to replace all 4 tyres at thje same time and rotate the regularly to keep wear even, but most owners are not even aware of this, never mind arsed doing anything about it, hence so many with dead transfer boxes or the prop removed, which will leave it as a front wheel drive car. Some shady cunt was selling false, freewheeling VCUs on ebay for a while so giving the visual impression of a complete, working 4wd system.

 

Flooring it on wet grass will provoke wheel spin, but which wheels spin is anyones guess and will not be the same each time as grip levels change, so not a good test. remember, the front and rear diffs are likely to be normal open diffs, so you could have both wheels on one side spinning while the other side do nothing....its really hard to tell anything useful like that.

 

I could literally bore you to the point where suicide seems like a reasonable option by talking at great length about the Freelander transmission system, but Im not sure where the similarities or differences are with the Subaru - you would be best to check out their owners club forum, assuming there is one.

[steve_earwig]

Here's one http://uk.subaruownersclub.com/forums/ looks like it's free. Hmm, they seem to have sections for everything apart from transmissions...

[DVee8]

Wet grass is a good way to find out or try this

 

http://www.youtube.com/watch?v=Up9kbyM1nwA&feature=youtu.be

[dollywobbler]

Can't say I've heard much about Subaru 4x4s going wrong. They're pretty tough. If you look on the internet, you'll find problems about pretty much everything.

[steve_earwig]

TBH the problem I usually associate with Subarus is knobs tuning* the engines until they go bang.

 

Wet grass is a good way to find out or try this

 

I can imagine it: "Can I take it for a test drive, and is there a muddy field near here?"

[crapcarcollector]

What dolly said. I had one with a gazillion miles on and had been "tuned by a specialist", 4WD Was as good as gold. Had to have the donkey rebuilt though....

[Bobthebeard]

If you look on the internet, you'll find problems about pretty much everything.

True!..... I recently searched the internet for 'foot pain'

Apparently I may have anything from scalp cancer to athletes foot....

[gordonbennet]

I've recently bought an H6 3 litre on an 02 plate, the 4WD system of that is slightly different to the one on the 2.0 and 2.5....one of the best forums is subaruoutback.org   very useful place indeed, mostly US and Aussie posters but the info there is simply superb, Outback is only a Legacy on longer springs and some plastic clip on body panels.

 

Basically if you jack a side up and turn a wheel out of gear, the other wheel that side should turn with it as its full time 4x4, that won't happen on the H6 which has a viscous coupling of some bloody sort so the one wheel can turn alone....does that make any sense, nah it doesn't to me either.

 

Generally Sub's are pretty robust things, one thing i like about them is that they are designed to be maintained, in fact compared to most cars they are a pleasure to work on...well except for changing the spark plugs which is  bastard of a job....you'll find dipsticks under the bonnet for auto gearbox and front diff oils as well as the engine (not sure if box and front diff/transfer box share oils on manuals), easy oil changes all round so no need to have wanked out manky 130k mile oily piss in any of the transmission.

 

4 pots can suffer OMGCHG probs, the 6's don't suffer as badly...4 pots are also cambelt driven, but as a NorthSouth engine a lot nicer bloody job than a poxy EastWest shoe horned in.

 

Rear subframes rust quite well or badly, so well worth checking that out and treating, brake discs corrode well and the rears score badly, but cheap as chips for good qual pattern parts...£134 Mintex discs/pads for all 4 wheels on an H6.

 

Check the front drive shafts, inner boots sit just above the twin front CATs, so heat buggers the boots and they split...piss easy DIY for a handy bloke, again these cars were made to be fixed not like modern euro shit only designed to be manufactured as cheaply as possible.

 

I'll be having another in due course.

 

edit...check exhaust, genuine  might well cost more than you pay for the car, mine will be getting a stainless custom jobbie in time.

[Asimo]

I have a 2004 Legacy with 5 speed manual transmission, the same 'box used in the previous model.

 

 

The centre differential splits torque equally between front and rear axles. This centre differential also has a viscous clutch in parallel. This is arranged to limit SPEED differences between rear and front axles. As this is a friction device it will overheat if massively abused by rear axle and front axle continually turning at different rates.

In normal use it's reputation is: reliable.

Just ensure tyres are all the same diameter. If you have to replace two only, put the new ones on diagonally, that will keep the front and rear axles at the same number of revs/mile. I am just about to get (edit -replace ) the car's third set of tyres, at 107,000miles

 

Automatics have a different arrangement, there is no direct drive to the rear axle, rear drive is brought in by a hydraulically modulated clutch controlled by software looking at wheel and engine sensors etc.

 

 

Legacys are like Volvos, saloons are bargains compared to the sought after estates.

Edited August 3, 2014 by Sorn Me

[Lankytim]

These sound quite appealing, did they make many diesel models?

[gordonbennet]

One other thing, the gearbox is heavy complete with transfer box, son and i changed the clutch on his Imprezza, whilst a very straightforward job it was seriously heavy and took both of us to manage it.

[Stanky]

Thanks everyone, especially Gordonbennet!

 

Good to know these things, I was looking at this one in particular:

 

http://www.aandtautos.co.uk/used-cars/subaru-legacy-2-5-gx-4dr-auto-bournemouth-201407015454177

 

so its cooked it head gasket at 112k, does that signify its been neglected (FSH seems to contradict this assumption) or just that HGF is par for the course on a big flat four? Also, what are the autos like? I'd imagine that with 160 lb/ft on hand, its not a chore having an auto, though I'd prefer a manual given the choice at identical price points.

 

I have a bit of a history of every car I own, no matter how long I own it for, requires a new exhaust, so what should I budget for a new manifold-back system? Is a custom stainless job a viable alternative? 

 

I have desire to buy a tuned one, or tune one that I have bought! All I want is a nice, relaxed cruiser that is a bit 'left field' - The Subaru Legacy seemed to tick a lot of boxes as well as being generally fairly rugged from what I can determine (and as attested to on here), so its currently top of the list. 

 

Thanks for the gearbox info Sorn Me, thats very interesting and very useful - I tend to buy tyres in 4s and rotate every 5000 miles to keep waer even. I managed to wring 27,000 miles out of my last set doing this, and they had all worn down to 2-3mm evenly. Obviously this is much more of a concern on a 4wd car like this than on a FWD rusty Nissan as pointed out by Dave21478. I understand the concept and it should just make me more alert to the tyre condition than I already am.

 

Lankytim, I believe the later ones did come with a diesel engine, and its a boxer diesel too for maximum obscurity points!

[Asimo]

All I have ever really wanted to change about mine is the 2.0 litre flat four for the 3.0litre flat six. 

 

I borrowed a Diesel Legacy for a day and I thought it was vile. Latest Legacy's have an electric parking brake and no flat 6 option.

Another brand down the pan?

[gordonbennet]

Exhaust, don't know for sure but i think MJI or some stainless mob out B'ham way (check fleabay) were doing cat back stainless for about £300 all in fitted for the 2.5's, that will be miles cheaper than OE...normal pattern parts seem to be more common for 2.0/2.5 than they do for 3.0.

 

OMGCHG sounds fairly regular on them, but how well this ones been fixed is anyones guess.

 

Auto boxes need regular oil changes, easy DIY but unless you get really involved with pumping new in old out simultaneously via oil cooler pipes with engine running (sod that for a game) its  a case of changing a single sumpful (5 litres) each time x3 and running in between...i've done that now and after each sumpful the gearchange was noticeably better...very smooth and robust box but like all auto boxes do not neglect...i shall do a single sumpfull annually from now on.

 

If you want relaxed cruiser you really want the H6 (had mine LPG'd), for tuning you want a grey Jap twin turbo jobbie where the sky is the limit.

 

Price wise, i paid just under £1100 for the 02 outback with 107k miles, 12 months ticket and 8 months tax...i reckon you could find a lower mileage saloon if you hunt around for that money, as Sorn Me notes the saloons just aint popular, though i really like them.

 

 

edit...leccy parking brake on the latest?, fook me thats off the list permanently.

[Stanky]

Sorn Me, what is the verdict on the 2.0 engine? Given that my employer currently funds my dinosaur juice habit I was looking at 2.5's out of perversity, though I notice there is only 25bhp between them.

 

Is the 2.0 underpowered for the weight of the car? 

 

The 3.0 H6 sounds excellent, though they seem to command a price premium over the flat-fours of either displacement. 

 

Changing oil is a job I con confidently handle, I will outsource more involved work such as cam belts and things, as well as safety-critical work like brakes to a mechanic. Do they require specialists to fettle them or can common or garden mechanics work out what is what? My pet mechanic is used to working on TVRs so I assume has more knowledge than a johnny-come-lately who can just about find the steering wheel on a focus.

 

Yes, as my daughter has grown up a bit now and we don't need to haul half of mothercare around with us when we go away for more than 6 hours I thought the saloon would suit me better, and as an added advantage they are somewhat cheaper than an equivalent estate, though I understand they maintain value as more farmers want them.

[dollywobbler]

My 1995 Legacy was a 2-litre. Went well, sounded fab, delivered 27mpg no matter how I drove it. Never better, never worse. They are thirsty old beasts sadly, and the diesel option came along well too late.

[Micrashed]

Do you really need a 4x4?

For the few days a year we have snow then....

 

and 

 

 

If the thought of AWD fills you with OMG £££££ KAOS then look for something 2WD, like 

 

[gordonbennet]

Outback H6 on ebay, bugger can never get the damned cut'n paste to load here, so number 301264403877 looks like a fair bet, i reckon £13/1400 should bag that with a bit o luck.

 

By the way, in the last couple of months Legacy selling prices on ebay have been increasing about this age, dunno why but cars which didn't sell even a month ago are now fetching decent money, might be worth waiting a while and see how things go.

[twosmoke300]

Dave , with reference to the freelander system . Do they all feel like the brakes are dragging on low speed manoeuvres ? Or have all the ones I've driven been buggerd ?

[Asimo]

The great thing about the drive going to all of the wheels all of the time is how civilised it is: no wheelspin, lurching, scrabbling or torque-steer in road driving. Ever.

Again, when you have to squeeze past others with nearside wheels up the bank or in the verge: no dramas at all, however wet and muddy. Snow is fun, amazing just how steep a hill has to be to stop it.

Stability at speed on wet and windy motorways is excellant as well, quite (proper)-Citroen like.

 

The 2.0 litre is a bit slow I suppose. Mine is the single cam per bank, 135hp job, 05 onwards they got more power from twice as many camshafts and some sort of variable valve timing. It is good on petrol though, 33 to 35 mpg which I think is ok. I have had mine for 7 years and I realy don't know what could replace it except perhaps another or a1989 Audi 100.

 

I think they are very easy to work on. As has been said, designed to be maintained. I have had no trouble getting stuff done although there is not the large aftermarket parts choice that Imprezas enjoy.

Agree that asking prices seem to be increasing.

[Pete-M]

Subaru 4x4 system is a good one. There's a gearbox dipstick between the intercooler and back of the left hand head as you're looking from the front of the car. Make sure it's at the level. If the rear diff doesn't whine or clunk then they're pretty strong.

 

Auto boxes aren't as strong as the manual. I don't know much about the low ratio box bits as mine didn't have them.

 

One thing with my WRX Impreza was the gearing is utterly crap at City shuffling.

 

Subarus are the only Japanese cars I've owned because I like the engineering. Cleverly designed. Changing the plugs and rocker cover gaskets is a fiddly awkward job. Cambelt is easier than it seems but you need locking tool.

[dave21478]

Dave , with reference to the freelander system . Do they all feel like the brakes are dragging on low speed manoeuvres ? Or have all the ones I've driven been buggerd ?

 

Reversing at full lock should feel like you have the handbrake on a couple of clicks and may need a tiny bit of throttle to get it to shift. This stiffness is the VCU slipping and is normal. If its too stiff - which is entirely subjective and the pedants on the landy forum will rant and argue for pages about what is "too stiff" - then the VCU is probably getting too tight and the transmission is winding up, almost like driving a disco with centre diff locked on the road. IMO if you have to give it more than a tickle of revs to reverse, then its starting to get too stiff. Bell engineering do reconditioned VCUs for about £200 so its a wise precaution if buying a freelander..

 

When its working as it should, its a bloody excellent system. As Sorn Me describes above....its just works with no interaction from the driver no matter what the conditions.

 

I mentioned before about some sketchers selling freewheeling VCUs on ebay. Well thanks to those twats, this was me the first time it snowed a few days after I fitted it......

 

[mat_the_cat]

No useful information whatsoever, but around 15 years ago my mate's parents had a Legacy estate, and when he'd passed his test they allowed him to drive it. He gave a few of us a lift to college one morning, and after he'd pulled over and popped into a shop I slipped the gearbox into low ratio 'for a bit of a laugh'. When he got back in, I started asking him how quickly it accelerated from a standstill...of course being 18 and full of testosterone he felt obliged to show me, and floored it. All I can say is that 0-10 mph was very impressive, but I almost nutted the dashboard when the rev limiter kicked in.

 

The Outback H6 on LPG is on my wish list, as I reckon that'd be an ideal car for me. Maybe one day?

[twosmoke300]

The dps system on hondas is pretty good . Occasional squealing noises that are cured with a couple of fluid changes

[twosmoke300]

The dps system on hondas is pretty good . Occasional squealing noises that are cured with a couple of fluid changes

[barefoot]

Chap next door has a newish diesel legacy and the gear box 'broke'.

It cost him just shy of £4,000 to sort but he was a little sketchy on the details.