JohnA
Forum Member
Had a fine time with the SH Forester and its new ADS drivetrain over Easter. The SH now has 1.447 low range, 444 final drive, standard 1-4 and a taller 5th that's a just touch lower thanks to that reduced final drive. There's now a 20kg fluid coupling and LSDs front and rear.
There was a bunch of other work done, as some deferred maintenance to get through. The only things not sorted were the bushings (not enough time to wait for parts to arrive ) and a seeping head gasket on the passenger side that will need to make a decision about, given the old blue coolant had turned a disconcerting shade of brown.
Pretty happy with the ratios – low first is great on broken ground and can be better relied on to manage mild downhills, while top gear seems only a couple of hundred rpm lower than before. Being a touch lower it's now much more flexible and pulls happily from near 60kmph onwards. Did not need to change down as much on typical windy, undulating country roads. On the freeway the speedo shows 120kmph at around 3050rpm, which am fine with - on backroads 100kmph comes up at 2500rpm - higher revs but closer to the sweet spot in terms of maintaining speed/revs on grades.
Being able to stay in 5th most the time improved fuel efficiency from around 8.2L/100 for a weekend away with 600km of combined driving that included freeway out of Sydney, over the Blue Mountains, country roads and plenty of dirt, to 7.4L/100. Was probably going a bit more gently and did not hit any trails but this much improved economy in mixed driving was totally unexpected. Pleased to find that traffic lights notwithstanding could stay in 5th almost the whole way over the mountains, discounting that steep-ish climb up to Wentworth Falls.
Also happy with the ratios in the inner city - can sit a gear higher - in 4th in a 40 zone, for instance. This makes things smoother and means fewer changes. It's possible to nearly stop and then go in 2nd, while 1st is now perfect for city laneways, even though it's a touch higher than the old 1LR used in those tight situations in the past. The lower gearing is also good in very slow moving traffic, which with the standard gearbox could be a bit of a pain.
No, I did not crawl under the car and stare at the 'new' gearbox for hours on end.
So far as I understand it, the helical LSD at the front balances power at the wheels and instantly adjusts to loss of grip by shifting power from the side losing traction using a bunch of fun worm gears. However it works, as soon as got into the car it felt like the steering was heavier - even stopped and checked the tyre pressures. The steering also pulls strongly back into a straight line in a way it did not used to. Am disposed to like this.
The car is more planted, not only on the dirt but on the tar. For instance, on the way down the mountains there's that bend at Lapstone before you get onto the freeway and I always felt the need to back off there. No longer. Kind of reminds me of driving an A4 Quattro or a Golf GTi, or a WRX, unlikely as any of that sounds - you can drive into a corner in the knowledge grip will be there.
My feeling is that the prior tendency to oversteer due to loss of grip (and the electronic management of such loss with automatic braking) has gone. The car now follows the front wheels with all its might and the R160 LSD pushes along behind with almost no tendency to step, even with one wheel in the gravel, even on corrugations. The weird mix of open diffs and electronic braking with the standard setup once had me going backwards down Snake Valley Creek in the mud with no driver input whatever, so pretty pleased with how it feels now.
Not certain which of the changes has enhanced handling so much - the 20kg coupling, the LSDs, my fevered imagination (guessing the LSDs, particularly the helical front), but whatever is going on, the SH is now a complete animal on dirt roads and very confidence inspiring.
Have not done any challenging fire trails yet but did bump around the place in 1st low range in order to get a feel for it - clearly it's going to be a significant enhancement. Running G15s and could not find anywhere to lose traction, even on wet grass. Be interested to see how she goes in the messy stuff, given I did not opt for the Cusco rear. Obviously, will not do so well with a corner in the air, or in the mud with complete loss of traction, but hopefully it will be much better than before.
More comments to follow...anyone else with a modified drivetrain, please weigh in!
There was a bunch of other work done, as some deferred maintenance to get through. The only things not sorted were the bushings (not enough time to wait for parts to arrive ) and a seeping head gasket on the passenger side that will need to make a decision about, given the old blue coolant had turned a disconcerting shade of brown.
Pretty happy with the ratios – low first is great on broken ground and can be better relied on to manage mild downhills, while top gear seems only a couple of hundred rpm lower than before. Being a touch lower it's now much more flexible and pulls happily from near 60kmph onwards. Did not need to change down as much on typical windy, undulating country roads. On the freeway the speedo shows 120kmph at around 3050rpm, which am fine with - on backroads 100kmph comes up at 2500rpm - higher revs but closer to the sweet spot in terms of maintaining speed/revs on grades.
Being able to stay in 5th most the time improved fuel efficiency from around 8.2L/100 for a weekend away with 600km of combined driving that included freeway out of Sydney, over the Blue Mountains, country roads and plenty of dirt, to 7.4L/100. Was probably going a bit more gently and did not hit any trails but this much improved economy in mixed driving was totally unexpected. Pleased to find that traffic lights notwithstanding could stay in 5th almost the whole way over the mountains, discounting that steep-ish climb up to Wentworth Falls.
Also happy with the ratios in the inner city - can sit a gear higher - in 4th in a 40 zone, for instance. This makes things smoother and means fewer changes. It's possible to nearly stop and then go in 2nd, while 1st is now perfect for city laneways, even though it's a touch higher than the old 1LR used in those tight situations in the past. The lower gearing is also good in very slow moving traffic, which with the standard gearbox could be a bit of a pain.
No, I did not crawl under the car and stare at the 'new' gearbox for hours on end.
So far as I understand it, the helical LSD at the front balances power at the wheels and instantly adjusts to loss of grip by shifting power from the side losing traction using a bunch of fun worm gears. However it works, as soon as got into the car it felt like the steering was heavier - even stopped and checked the tyre pressures. The steering also pulls strongly back into a straight line in a way it did not used to. Am disposed to like this.
The car is more planted, not only on the dirt but on the tar. For instance, on the way down the mountains there's that bend at Lapstone before you get onto the freeway and I always felt the need to back off there. No longer. Kind of reminds me of driving an A4 Quattro or a Golf GTi, or a WRX, unlikely as any of that sounds - you can drive into a corner in the knowledge grip will be there.
My feeling is that the prior tendency to oversteer due to loss of grip (and the electronic management of such loss with automatic braking) has gone. The car now follows the front wheels with all its might and the R160 LSD pushes along behind with almost no tendency to step, even with one wheel in the gravel, even on corrugations. The weird mix of open diffs and electronic braking with the standard setup once had me going backwards down Snake Valley Creek in the mud with no driver input whatever, so pretty pleased with how it feels now.
Not certain which of the changes has enhanced handling so much - the 20kg coupling, the LSDs, my fevered imagination (guessing the LSDs, particularly the helical front), but whatever is going on, the SH is now a complete animal on dirt roads and very confidence inspiring.
Have not done any challenging fire trails yet but did bump around the place in 1st low range in order to get a feel for it - clearly it's going to be a significant enhancement. Running G15s and could not find anywhere to lose traction, even on wet grass. Be interested to see how she goes in the messy stuff, given I did not opt for the Cusco rear. Obviously, will not do so well with a corner in the air, or in the mud with complete loss of traction, but hopefully it will be much better than before.
More comments to follow...anyone else with a modified drivetrain, please weigh in!
