Oz Isuzu Forums
General Boards => Off Topic => Topic started by: tess on Nov 17, 2017, 02:12:11 PM
-
Ok so you know how you see vehicles submerged in water at boat ramps and you wonder how that's possible........well it's quite easy as it turns out :)
Lake tyers conc ramp, reversed down a Colorado until the rear wheels were in the water about 50mm deep as the trailer is easily loaded deeper. I had handbrake and in park, walked to the rear to help land the boat....nxt minute shes sliding.....fark, luckily the trailer jack knifed which stopped it being fully submerged. It got up to 2/3 up doors, so i jumped in through the window and egaged 4wd and drove it out. The ramp was really slimy.
My question......if it was in 4wd parked as above would the front wheels provide traction ie would it have still slid in ?
-
Not.my vehicle btw....... :headbang:
-
Haven't launched the boat with the Isuzu yet but when using the Falcon (auto) handbrake on and transmission in park.
-
Ninja edit, it was in park not drive oops
-
Good question that. Suspect it would work but would like to hear from an expert.
-
:worthles:
Was it slimy under the front wheels as well as the back wheels?
-
:worthles:
Was it slimy under the front wheels as well as the back wheels?
Haha, yeah well my phone was in my pocket and is now deceased......so no pics.
Perfect concrete ramp with great grip, just the rear wheels in about 25_50mm of water. You struggled to stand up on it, this was not known until this all happened. There is a raging debate about this exact same situtation on a FB page, great question i think.
-
The idea of using 4WD is so you utilize the grip available from 4 tyres and not two tyres only.
The drive and/or the handbrake effect and if in park means the retardation or drive available is to all wheels. The fronts with less weight would have a litle less grip but will at least have additional grip to add to the lessened rear grip.
Didn't anyone check the underwater surface first???
What tyres were on the vehicle? Some will cut through crap better than others.
If you have 4wd, why wouldn't you use it. Experience is a great teacher. Foresight is also an advantage as is thinking about what you are going to do.
-
Used this ramp prob 30 times before, have pulled my 1.6t boat out with our vf commodore in same ramp so 4wd is not required.
Ute had road tyres and we launched there same morning, you must not be around boats much.
Only difference over past launch and retieves is i got out to help land it as it was windy as hell.
-
..................... Experience is a great teacher................
Experience is something I always seemed to get a split second after I really needed it.
-
Hindsight is a wonderful thing. I have always used four wheel drive on ramps if in a 4x4. If on a busy ramp some people roar up the ramp after loading their boat and drag water all the way to the top making it very slick. Even the best concrete ramps get slippery. Great save Tess , would have had the heart pounding on that one.
Cheers Shane
-
If it's in Park with the handbrake on it wouldn't make any difference if 4wd was selected or not. The vehicle is stationary with no drive to the wheels. On a slippery ramp it would almost have to be the weight of the trailer/vehicle overcame the grip (friction) of the tyres. I would think tyre choice would have to be more the culprit.
Al.
-
If it's in Park with the handbrake on it wouldn't make any difference if 4wd was selected or not. The vehicle is stationary with no drive to the wheels. On a slippery ramp it would almost have to be the weight of the trailer/vehicle overcame the grip (friction) of the tyres. I would think tyre choice would have to be more the culprit.
Al.
Yeah i agree, but if it was in drive with handbrake on it would have stayed put. I think ;D
-
Tess
What has me not being around boats much, or plenty of times, have to do with wise checking of the surrounds.
Sometimes there could be crocodiles to bite you, other times there isn’t, still best to check the surrounds and use what is available to you.
-
Tess
What has me not being around boats much, or plenty of times, have to do with wise checking of the surrounds.
Sometimes there could be crocodiles to bite you, other times there isn’t, still best to check the surrounds and use what is available to you.
Ahhh yes grasshopper.......sometimes you don't need to check for crocs as you know they're not there :headbang:
-
For what it's worth I never trust my handbrakes when on a steep slope, whether a ramp or out bush getting through a gate. I always put the manual box in 1st and turn the engine off. I've seen a couple of vehicles roll back when in neutral with handbrake on. Not worth it.
-
So it seems your vehicle slipped on something which wasn't there and slid into the water. In 4wd might help with that!
-
So it seems your vehicle slipped on something which wasn't there and slid into the water. In 4wd might help with that!
Not quite correct
1. No crocs so didn't check for them
2. Not my vehicle, many other trailers in carpark, some cars, I'd say we were in deeper than most due to trailer height.
3. Slime was there 8 hours prior so
no need to check for slime or crocs, as far as im aware crocs dont reside south of Brisvegas
4. Now you're getting closer to topic at hand, would it have slipped into croc infested water if it was in 4wd, in park, handbrake on ?
;D
-
I mentioned if in 4wd it would provide more traction and hold the vehicle, if slippery. You placed it in 4WD and then had more traction and drove it out. You answered your own question.
-
Thank you kind sir.
-
But it's 4 wheel DRIVE, not 4 wheel PARK. If it's in Park, there won't be drive going to the wheels. Rev the car in Park and it doesn't go anywhere. Same as Neutral but it would roll away. Only thing i would think is previous times when you have stayed in the vehicle is you have kept the transmission in Drive, thus keeping drive to the wheels/tyres.
Al.
-
Hell yes!
if it was in 4wd and in park all wheels would be connected to the gearbox which is locked in park
-
OK, this is how I would look at it, let’s say you have 2H selected and you are parked on a slope with the vehicle in “park” and the handbrake off. You decide to stick your trolley jack under rear diff and jack the car up. It will roll away won’t it. If you do the same thing but have 4H or 4L selected the car won’t roll away - yes?
The tyres provide a degree of grip up to a point where enough “slipriness” will cause them to let go. If you were to slowly increase the degree of slipriness, wouldn’t 4 lots of grip hold the same car still for longer than 2 lots of grip?
I’m loving the new word of the day - slipriness:)
Cheers
Martin
-
That's a very non-technical term Martin. What we really need to know is the coefficient of friction for:
- boat ramp - dry
- boat ramp - wet
- boat ramp - covered in lots of slimy stuff
A great analogy by the way. I am now able to wrap my head around this dilemma.
Thanks
-
The boat ramp could be called a slipway I suppose., able to launch anything into the water just using gravity.
-
Being a engineer i could supply the comps, on the 2nd bottle od red so can't be stuffed. ;D
Aaannnd, if this happened in croc water this debate would be dead, much like the Colorado.......tidal water :icon_salut:
-
Hell yes!
if it was in 4wd and in park all wheels would be connected to the gearbox which is locked in park
That's the way I understand it to be........rightly or wrongly.