Jump to content

4l60e question

tonyt915

By tonyt915
in Ask A GM Technician

Recommended Posts

tonyt915 Enthusiast

tonyt915

Posted
Posted

ok found out i do have a 4l60e in the truck and also found somthinelse out is the tow/haul button supposed to dissengage o/d in the final gear? i was doing 60 and pushed it but nothing happened. i slowed to 50 and hit still nothing, but when i take off say around 30 it will work is this normal or is there something wrong or is this normal

GM-Tech Senior Enthusiast

GM-Tech

Posted
Posted

Here's the official description and operation from our service information. Please show me where it says it locks out O/D.

 

 

 

Tow/Haul Mode

Applies to the following models:

 

• 2000-2004 C/K Utility Models

 

• 1999-2004 Chevrolet and GMC C/K Pickup Models (Silverado and Sierra)

 

• 1999-2002 GMC S/T Utility Models (Jimmy and Envoy-Old Style)

 

 

PURPOSE

 

 

• Reduce the frequency and improve the predictability of transmission shifts when pulling a heavy trailer or a large or heavy load. This is most apparent in city traffic. Without tow/haul, the transmission may upshift on a closed throttle decel. With tow/haul, the transmission will hold the current gear on a closed throttle decel. This reduces upshifts and downshifts.

 

• Provide the same solid shift feel when pulling a heavy trailer or a large or heavy load as when the vehicle is unloaded.

 

• Improve control of vehicle speed while requiring less throttle pedal activity when pulling a heavy trailer or a large or heavy load.

 

 

ACTIVATION

 

 

• Tow/Haul is selected or de-selected via a switch on the end of the transmission shift lever for all models except the GMC Jimmy and Envoy, their switch is mounted on the shift console. A light on the instrument panel will illuminate to indicate that tow/haul has been selected.

 

• Tow/Haul must be reselected every time the vehicle is started (if desired).

 

 

FUNCTION

 

 

• Tow/haul is designed to be most effective when the vehicle and trailer combined weight is at least 75% of the vehicle's Gross Combined Weight Rating (GCWR).

 

• Operation of tow/haul in a lightly loaded or non-loaded vehicle will not cause damage. However, there is no benefit to the selection of tow/haul when the vehicle is unloaded, this situation will cause a firm shift. The tow/haul switch is not a performance switch.

 

• Selection of tow/haul when unloaded may result in unpleasant engine and transmission driving characteristics and reduced fuel economy. Tow/haul is recommend only when pulling a heavy trailer or a large or heavy load.

 

• Examples of altered shift speeds when in tow/haul:

 

- Minimum 1-2 shifts pushed out approximately 13 km/h (8 mph)

 

- Minimum 2-3 shifts pushed out approximately 24 km/h (15 mph)

 

- Minimum 3-4 shifts pushed out approximately 48 km/h (30 mph)

 

- Tow/haul only affects shift points below 88 km/h (55 mph).

 

Refer to vehicle Owner's Manual for further information regarding tow/haul mode.

Nice rig Enthusiast

Nice rig

Posted
Posted

When I pull my boat with tow/haul, I have to get up to 65mph before overdrive kicks in...that's the reason I pretty much keep it in 3rd unless I have a nice long flat stretch of road.

95Sierra2500 Senior Enthusiast

95Sierra2500

Posted
Posted
No, Tow/Haul does not lock out O/D or any gear for that matter.  It just modifies the shift characteristics.

 

 

 

 

Hmmm...then my impression of it was wrong...Maybe it's just because the only thing I've ever driven w/a tow/haul mode was a Ford...and it DOES lock you out of O/D.

Archived

This topic is now archived and is closed to further replies.

Go to topic listing
×
×
  • Create New...