What transmission: 2004 Workhorse P32 chassis

[glennr]

I am having an issue with my transmission.  2004 Workhorse P32 chassis, 8.1 engine and cannot find what transmission was installed in this unit.  I've seen Allison, and been told Hydramatic, so where can this question be answered?  All the paperwork I have tells most everything about the unit except the type of transmission. Would like to do some research on the issue before going for services.  The issue,  when travelling at a steady speed, constant throttle, with or without cruise engaged the transmission "flares" on the downshift or overdrive disengagement.  If cruise is engaged, tapping the brake pedal or manually shifting out of overdrive allows the unit to immediately "lock" into gear and flaring stops.  

[wolfe10]

My information shows that starting in 2003, the P chassis used the GM 4L85E.

[Toolio]

We also have the 2004 Workhorse P chassis with the 8.1 litre engine. The transmission is an Allison model 1000, 6 speed with overdrive, rather than the GM 4L85E

[wolfe10]

Toolio,

Welcome to the FMCA Forum.

I did a little more research and found this: http://www.deserttruckservice.com/pdf folder/workhorse_chassis.guide.pdf

Just to confirm, the 6th digit of your VIN is a 5 (P chassis), not 6 (W chassis) and you have confirmed Allison transmission (external spin on oil filter) and tag on transmission indicates the 1000 series. Very interesting.

 

Page 36 says the Allison transmission is used in the W chassis, not P- again no first hand information on this:

 

Workhorse utilizes to types of transmissions depending on the Series of the chassis. The P Series chassis utilized the

GM Hydra-Matic 4L80-E 4-speed automatic transmission on all chassis in the 1999-2002 model year chassis. In the 2003 model year GM introduced the 4L85-E Hydra-Matic transmission, a heavy-duty version of the 4L80-E. The 4L85-E became standard in all P Series chassis with the 8.1Lengine. Prior to the 2006 model year the W Series 20,700 lb. and 22,000 lb. GVWR chassis used the Allison™ LCT 1000 or 1000MH 5-speed automatic transmission while the W Series 24,000 lb. GVWR chassis used the Allison™ 2100MH 5-speed automatic transmission. Beginning with 2006 model year all Allison™ transmissions will provide 6 forward speeds.

[dickandlois]

Things are very confusing when it comes to transmissions used over a 4 year time line ( and that gets muddied even more depending on engine options - when you through in the 6 L, not used hear for one coach - but not sure about the other.

Could the original posters please inform the forum as to how many forward gears they have ?

We might be able to brake it down this way

                    GM - 4L185 has 4 speeds with over drive and most likely equipped with a Tow / Haul button.?

                     The Allison 1000 series has 5 speeds with 1 overdrive.

                       The Allison 2000 series has 6 speeds with 2 overdrives.

I have a number of the electrical and chassis drawings But the Chassis W series is different by year and over all length.

To Make things more confusing - there is no mention of what transmission was used. 

As Brett might say, Not in my pay grade LOL

Rich.

[f442485]

Glennr, take your vin (all digits) and call any GM dealership and they can tell you what trans you have in that particular year and chassis