Hey guys, from my reading I have found out that the 6speed manual tranny has a lower crawl ratio compared to the automatic. Does this generally mean that the manual can operate at 1mph going up a somewhat moderate incline/decline without stalling and fiddling with the clutch? I know im not being too clear, I guess what I would also like to know what specifically the crawl ratio means. Thanks again for any help or input.
In addition to what CaliChoas has posted, you need to be mindful that Atrac will not work once you're on the clutch. In order to craw at 1mph without being in the clutch, you'll need a dual case setup like the Inchworm Lefty or Marlin Cralwer's MC11 (which is status unknown at the moment).
Quote:
Crawl Ratio-Wikipedia previously said:
Crawl ratio is a term used in the automotive world to describe the lowest gear ratio a vehicle is capable of. The crawl ratio of a vehicle is affected by the entire drive train, including transmission, overdrive differential and tires, and can vary greatly between automobiles.
The lowest gear of most vehicles is either first gear or reverse, but when referring to crawl ratios, only first is normally taken into consideration. The crawl ratio is aptly named, for when a car is using its lowest possible gearing, it moves the slowest at a particular engine rpm. The usefullness of a high crawl ratio is to provide the driver with the greatest possible torque to pull large loads or climb steep inclines. Crawl ratios are most often used in the context of large SUVs or trucks and off-road vehicles.
__________________
Click for the "Genie" build up
Sandoo Blue FJ
Walker Evans adj. F&R reservoir shocks. Pro Links. AP F&R bumpers. Demello skid. Mile Marker SE9500C. Viking Trail Line. Super Swamper LTB 34s on Tacoma wheels. 305 MTR on Wheelers wheels. Trail Gear Sliders, Aeroflow, Lightforce Blitz 240, Powertank 10lb, Hi-Lift, Jack Mate, Pull-Pal.
You can certainly 'crawl' uphill slower with an auto, since you can ride the brakes to control your speed. We've had both & prefer the MT for crawling down the steep trails in CO, I'm now much more comfortable with the MT than I was with the AT.
Location: I ain't like them, but I can pretend <<<=8)
Posts: 2,103
Re: Low crawl ratio
I agree.. Downhill was much less scary with my manual Rubicon than my current AT FJ.. Ron
Quote:
shane4x4 previously said:
You can certainly 'crawl' uphill slower with an auto, since you can ride the brakes to control your speed. We've had both & prefer the MT for crawling down the steep trails in CO, I'm now much more comfortable with the MT than I was with the AT.
__________________
08 SS, SS valve stem caps and exhaust tip
Rapper standing on the corner, wrappers flying in the wind... And in my quite reflection, I wonder why..
Location: Parker County, TX and Santa Fe County, NM
Posts: 2,345
Re: Low crawl ratio
Quote:
shane4x4 previously said:
You can certainly 'crawl' uphill slower with an auto, since you can ride the brakes to control your speed.
The other advantage of an AT in an uphill crawl is the torque converter. Since it doesn't lock up in lower gears or low speed, you get some additional low speed control over and above the mechanical gearing. It's not mechanically efficient (wasting energy by dissipating heat), but for a truck as powerful as the FJC it works pretty well. I've heard claims that the torque converter essentially doubles your crawl ratio but have never seen any hard proof of that figure and am a little skeptical myself.
__________________ All men dream: but not equally. Those who dream by night in the dusty recesses of their minds wake in the day to find that it was vanity: but the dreamers of the day are dangerous men, for they may act their dreams with open eyes, to make it possible - T. E. Lawrence
when your riding the clutch and atrac isnt engaging how much of a downside is this?
Since I have the MT I will answer it for you.
I say zero Down side, I essentially do the same thing that A-Trac does while heal toeing so A-Trac is a wast if you know how to use all 3 pedals at the same time since you are doing what it is, applying the brakes to force the other wheel(s) to spin. I turn on A-trac every now and again just to play with it and the only time I've found it to be useful is on a hill climb that isn't crazy steep were you can go up the hill with just a little gas and no feathering of the clutch. The locker on the other hand is great and has been very handy.
__________________ "Because in the end it has almost nothing to do with the bike and everything to do with setting
out to accomplish something that is intimidating, that is unknown to you, something you know you
have a good chance of failing at but doing it anyways and slowly but surely proving yourself wrong." Mike Ambs
www.corva.org "Those who expect to reap the blessings of freedom must undergo the fatigue of supporting it."
- Thomas Paine
I say zero Down side, I essentially do the same thing that A-Trac does while heal toeing so A-Trac is a wast if you know how to use all 3 pedals at the same time since you are doing what it is, applying the brakes to force the other wheel(s) to spin. I turn on A-trac every now and again just to play with it and the only time I've found it to be useful is on a hill climb that isn't crazy steep were you can go up the hill with just a little gas and no feathering of the clutch. The locker on the other hand is great and has been very handy.
I sort of understand what you're saying, but you're not exactly doing what Atrac is doing. When there's slippage, atrac can drive the wheel with traction while braking the one without. When you use the brakes manually, you can't selectively apply the brakes to each wheel. ABS sensors can detect slippage and apply the brakes to the one spinning-until both wheels are going at teh same speed.
__________________
Click for the "Genie" build up
Sandoo Blue FJ
Walker Evans adj. F&R reservoir shocks. Pro Links. AP F&R bumpers. Demello skid. Mile Marker SE9500C. Viking Trail Line. Super Swamper LTB 34s on Tacoma wheels. 305 MTR on Wheelers wheels. Trail Gear Sliders, Aeroflow, Lightforce Blitz 240, Powertank 10lb, Hi-Lift, Jack Mate, Pull-Pal.
Linear Mode
