Allison valve body for 2000, remanufactured and ready to install. Ships fast from the USA.
A Duramax-equipped Silverado or Sierra 2500/3500 HD that hunts for gears, flares into second, or drops into failsafe with a P0872 code is usually pointing at the valve body long before it is pointing at the clutches. This remanufactured unit is built to the 2004-2005 Allison 1000/2000 casting - the five-speed generation that added a seventh solenoid - so you are installing a verified, tested assembly instead of gambling on a worn core.
The Allison 2000 badge is GM's heavier-duty rating of the same Allison 1000/2000/2400 valve body family used across the Duramax lineup, not a different casting. Inside, the valve body is a stack of precision bores and spool valves bolted between the pump and the clutch packs. It takes the line pressure the pump generates and routes it, through the shift and pressure-control solenoids mounted on the body, to whichever clutch the TCM has selected for the current gear. On this 2004-2005 casting, a seventh solenoid - solenoid G - was added to bleed line pressure down at idle and during light-throttle cruising, which is the detail that separates this version from the six-solenoid 2001-2003 unit.
Pull codes first. A P0872 points at the sticking E-shift valve bore described above and is the single most common failure on this generation; a P0741 with TCC surge or overheating fluid points at the F-trim valve sleeve instead. Our Allison 1000 valve body problems and testing guide walks through the vacuum and air checks used to confirm either fault before condemning the whole valve body, since a stuck solenoid or a wiring fault can mimic the same codes.
This unit matches the 2004-2005 five-speed casting: a 7-solenoid body with one tube on the bottom and no second tube hole in the modulated main pressure housing, which is what sets it apart from the 2006-2009 two-tube version and the tubeless 2010-up redesign. Allison 2000 and Allison 1000 share this same casting family across the Duramax 2500/3500 HD lineup, so the badge on your truck does not change which valve body fits. Confirm your build date is inside the 2004-2005 window before ordering, since the earlier 2001-2003 six-solenoid casting and the later six-speed units will not interchange - send us your year, make and model or check the full Allison transmission parts collection if you are not certain which generation you have.
Drop the pan and change the filter in the same job so wear debris from the old valve body does not recirculate through the new one, and torque the mounting bolts down in sequence since these halves run without a separator plate gasket and an uneven clamp load is enough to cross-leak pressure between circuits. Run on TransSynd or Dexron VI ATF; our Allison 1000 fluid and filter service guide covers the move to TES 668 and current capacities if you are topping off an older fill. After the swap, clear codes and run the adaptive relearn through a mix of light and moderate throttle - a heavy-duty Allison scan tool makes that relearn and any follow-up code check far faster than driving it out. If the pan has never been swapped for the deep version, pairing this job with a deep transmission pan adds fluid capacity and cooling margin for a truck that tows.
| Transmission | Allison |
| Year Range | 2000 |
| Condition | Remanufactured / updated |
| Shipping | Ships from the USA |
Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
No. Allison 2000 is GM's heavier-duty rating of the same 1000/2000/2400 casting family, so this 2004-2005 valve body fits either badge. What matters for fitment is your build date, not whether the truck is marked 1000 or 2000.
Solenoid G, added starting in 2004, bleeds line pressure down at idle and during light-throttle cruising. It's the detail that separates this casting from the 6-solenoid 2001-2003 version.
P0872 from a sticking E-shift valve bore is the most common fault on this generation, followed by P0741 with torque converter clutch surge or slip from a worn F-trim valve sleeve on earlier-build units.
Yes. It ships as a complete remanufactured assembly with the shift and pressure control solenoids already mounted and tested.
Change the fluid and filter in the same job, torque the mounting bolts in sequence, clear codes, and run the adaptive relearn through light and moderate throttle before judging the shift quality.
Send your year, make and model, or your VIN, before ordering. The 2001-2003 and 2006-2009 castings use a different solenoid count and tube configuration and will not interchange.
