1st. year of 8.1 & Auto-Park unit under the hood.

frederick w · 12-20-2011, 07:04 PM

What year was the 8.1 first introduced in a MH?

When did they move the auto-park unit to the front of the eng. compartment?

Thanks again and Merry Christmas

ga traveler · 12-20-2011, 07:19 PM

Quote:

Originally Posted by frederick w

What year was the 8.1 first introduced in a MH?

When did they move the auto-park unit to the front of the eng. compartment?

Thanks again and Merry Christmas

I had a 1995 P30 with the auto park brake. The 1993 used a auto. but it used the power steering pump. I think the 8.1 came out in 1999.

DriVer · 12-21-2011, 08:55 AM

Quote:

Originally Posted by frederick w

What year was the 8.1 first introduced in a MH?

The 8.1L GM Vortec was introduced in 2001.

Quote:

When did they move the auto-park unit to the front of the eng. compartment?

The J71 Auto Apply Parking Brake (AAPB) was created by GM (a long time ago) to meet a very stringent Federally mandated specification. When GM sold the motorhome division off in 1999, Workhorse owned that system from that point forward, including the parts inventories and several dozens of motorhome division employees. The J71 was used continuously in the P Series until it's cease of production in 2005.

The W24 uses a J72 AAPB which is much more reliable, has exponentially fewer points of failure and meets Federally mandated specifications for parking brake equipment on Class 6 vehicles equipped with hydraulic brakes. In the later years beginning in 2006, Allison provided Workhorse with a parking pawl in the 2000 series transmission and the J72 was dropped. The W18 continues to use the J72 AAPB.

The UFO is equipped with an AAPB as well however it is a rear engine chassis and as such is a requirement. The UFO uses Arvin Meritor HPB system and the AAPB is integrated into that system and is not a stand alone system like the J72.