Dumb 4x4 question
#21
01-20-2010, 04:58 PM
Ridiculously Active Enthusiast
Join Date: Sep 2006
Location: Beautiful Pacific NW
Posts: 1,678
Re: Dumb 4x4 question
But to answer your question: Yes, absolutely, with even the slightest level of front wheelspin/slip TC will INSTANTLY dethrottle the engine (HSD drive system) and begin "hammering" the brakes.
Last edited by wwest; 01-20-2010 at 05:05 PM.
#22
01-20-2010, 05:03 PM
Ridiculously Active Enthusiast
Join Date: Sep 2006
Location: Beautiful Pacific NW
Posts: 1,678
Re: Dumb 4x4 question
Well, yes and no.
Help, in this case, is a rather subjective term. Many owners would undoubtedly agree with me that TC is more often a hindrance (PITA, really) rather than a "help".
#23
01-20-2010, 05:07 PM
Ridiculously Active Enthusiast
Join Date: Sep 2006
Location: Beautiful Pacific NW
Posts: 1,678
Re: Dumb 4x4 question
Read this Willard, the '09 FEH was the first FEH with SC and TC.
"The Escape has respectable if not exciting performance. It's certainly no sports car, but it has no trouble accelerating up to merge with freeway traffic. The steering feel is responsive and nicely weighted with no slop in the mechanism. The brakes had good pedal feel and were easily modulated. The standard Escape has a conventional hydraulic friction brake system with a vacuum booster and gets Roll Stability Control with traction control as standard equipment. The hybrid has regenerative braking that is blended with the friction braking. The electro-hydraulic brake system which is used to provide this functionality only has ABS with no traction or stability control making this the only SUV in the Ford lineup lacking that capability. Applying the throttle too aggressively on lower friction surfaces can get the front wheels spinning freely and you definitely don't want to take corners too aggressively."
http://green.autoblog.com/2007/06/05...escape-hybrid/
"The Escape has respectable if not exciting performance. It's certainly no sports car, but it has no trouble accelerating up to merge with freeway traffic. The steering feel is responsive and nicely weighted with no slop in the mechanism. The brakes had good pedal feel and were easily modulated. The standard Escape has a conventional hydraulic friction brake system with a vacuum booster and gets Roll Stability Control with traction control as standard equipment. The hybrid has regenerative braking that is blended with the friction braking. The electro-hydraulic brake system which is used to provide this functionality only has ABS with no traction or stability control making this the only SUV in the Ford lineup lacking that capability. Applying the throttle too aggressively on lower friction surfaces can get the front wheels spinning freely and you definitely don't want to take corners too aggressively."
http://green.autoblog.com/2007/06/05...escape-hybrid/
Last edited by wwest; 01-21-2010 at 05:04 AM.
#24
01-21-2010, 03:19 AM
Re: Dumb 4x4 question
TC isn't always a good thing, If you have time check out a similar discussion the lexus owners club hybrid section). People report not being able to go up slight inclines with the 400h. Almost caused me almost not to buy my wife one, but we don't get rediculous amount here in sunny St. Louis
#25
01-21-2010, 05:12 AM
Ridiculously Active Enthusiast
Join Date: Sep 2006
Location: Beautiful Pacific NW
Posts: 1,678
Re: Dumb 4x4 question
TC isn't always a good thing, If you have time check out a similar discussion the lexus owners club hybrid section). People report not being able to go up slight inclines with the 400h. Almost caused me almost not to buy my wife one, but we don't get rediculous amount here in sunny St. Louis
And then throw in TC inexpensively for "forcing" torque reapportionment and implementing a "virtual" rear LSD for the few buyers who aren't buying "it".
Least we forget it was Mercedes Benz, the ML320, that first introduced this flawed F/awd system.
Last edited by wwest; 01-21-2010 at 05:14 AM.
#26
01-21-2010, 12:59 PM
Re: Dumb 4x4 question
The following is from a Ford WorkShop Manual under AWD Function Tests.
What do you gather from this test?
A7 CHECK FOR TORQUE AT REAR WHEELS USING PWM OUTPUT CONTROL COMMAND #1 (CLCH_SOL) ACTIVE COMMAND
END the active command. The concern can not be duplicated at this time. RETURN the vehicle to the customer.
No
END the active command. CHECK that the driveshaft rotates when the transaxle is in gear. If yes, GO to Pinpoint Test D. If no, CHECK the Power Transfer Unit (PTU). REFER to Section 308-07B.
What do you gather from this test?
A7 CHECK FOR TORQUE AT REAR WHEELS USING PWM OUTPUT CONTROL COMMAND #1 (CLCH_SOL) ACTIVE COMMAND
- Enter the following diagnostic mode on the scan tool: DataLogger — 4X4 Control Module.
- Using the scan tool, command CLCH_ SOL to energize the ATC solenoid to a constant 100% applied.
- Drive the vehicle in a fully locked turn, on dry pavement, at 8 km/h (5 mph).
- Does the vehicle bind in the turn or resist turning?
END the active command. The concern can not be duplicated at this time. RETURN the vehicle to the customer.
No
END the active command. CHECK that the driveshaft rotates when the transaxle is in gear. If yes, GO to Pinpoint Test D. If no, CHECK the Power Transfer Unit (PTU). REFER to Section 308-07B.
#27
01-21-2010, 03:39 PM
Re: Dumb 4x4 question
If you want to sell the public FWD vehicles, patently UNSAFE FWD vehicles for wintertime adverse roadbed conditions,....
Like season allergies, posts about unsafe FWD vehicle appear in the colder months. Consider it nothing more than "more from fantasyland" as the poster drives just such a vehicle.
Like season allergies, posts about unsafe FWD vehicle appear in the colder months. Consider it nothing more than "more from fantasyland" as the poster drives just such a vehicle.
#28
01-21-2010, 03:48 PM
Ridiculously Active Enthusiast
Join Date: Sep 2006
Location: Beautiful Pacific NW
Posts: 1,678
Re: Dumb 4x4 question
With a fully locked rear drive then driveline windup and/or tire scrubbing will be at its worse in a tight turn on a highly tractive surface, the tighter the better. Vibratory feedback to the stearing wheel will be, might be, extreme.
The only thing missing is a caution note to the mechanic/technician to grip the stearing wheel only lightly and be sure and keep his/her thumbs on the outside of the stearing wheel rim.
"RETURN the vehicle to the customer.."
Pretty INCOMPLETE test if "that's" it. Nothing to indicate that the F/awd control module is using the correct level of "lockup" in the various circumstances required.
The only thing missing is a caution note to the mechanic/technician to grip the stearing wheel only lightly and be sure and keep his/her thumbs on the outside of the stearing wheel rim.
"RETURN the vehicle to the customer.."
Pretty INCOMPLETE test if "that's" it. Nothing to indicate that the F/awd control module is using the correct level of "lockup" in the various circumstances required.
#29
01-21-2010, 07:58 PM
Re: Dumb 4x4 question
With a fully locked rear drive then driveline windup and/or tire scrubbing will be at its worse in a tight turn on a highly tractive surface, the tighter the better. Vibratory feedback to the stearing wheel will be, might be, extreme.
The only thing missing is a caution note to the mechanic/technician to grip the stearing wheel only lightly and be sure and keep his/her thumbs on the outside of the stearing wheel rim.
"RETURN the vehicle to the customer.."
Pretty INCOMPLETE test if "that's" it. Nothing to indicate that the F/awd control module is using the correct level of "lockup" in the various circumstances required.
The only thing missing is a caution note to the mechanic/technician to grip the stearing wheel only lightly and be sure and keep his/her thumbs on the outside of the stearing wheel rim.
"RETURN the vehicle to the customer.."
Pretty INCOMPLETE test if "that's" it. Nothing to indicate that the F/awd control module is using the correct level of "lockup" in the various circumstances required.
#30
01-22-2010, 09:37 AM
Ridiculously Active Enthusiast
Join Date: Sep 2006
Location: Beautiful Pacific NW
Posts: 1,678
Re: Dumb 4x4 question
Proves...no.
You could have a center diff'l with an integral electromagentic clutch to bypass/lock it and the test, and the test results, might be exactly the same. But in point of fact the FE/FEH do have a PTO, these do not have center diff'ls.
You could have a center diff'l with an integral electromagentic clutch to bypass/lock it and the test, and the test results, might be exactly the same. But in point of fact the FE/FEH do have a PTO, these do not have center diff'ls.
Last edited by wwest; 01-23-2010 at 06:58 AM.
