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Allison 1000 transmission
Lifetime warranty. Upfront pricing. No surprises.
The Allison 1000 is the automatic GM paired with the Duramax diesel in its heavy-duty pickups for nearly twenty years. It is a strong transmission, and the ones on the road now have a lot of hard miles on them.
Which vehicles have an Allison 1000?
- Chevrolet Silverado 2500HD and 3500HD Duramax, 2001 to 2019
- GMC Sierra 2500HD and 3500HD Duramax, 2001 to 2019
- Some GM heavy-duty gas trucks
Signs your Allison 1000 is failing
- Slipping or flaring between gears
- Harsh or erratic shifts
- Limp mode
- Shudder or slipping when towing
- Problems that start after a tune or added power
Added power and heavy towing find the weak points in an Allison fast. Henry builds for how the truck is actually used.
Drop it off by 8, diagnosed today
Bring it in by 8 on a weekday and you have a diagnosis and a decision on your Allison 1000 the same day. Every time. Parts come direct from the manufacturer, usually within 24 hours, and the valve body is built here, not back-ordered.
Upfront price: call (919) 836-8820 for your Allison 1000 price, installed, before any work starts.
How Henry builds an Allison 1000
- Every known weak point upgraded. Each model has parts that are known to fail. They are upgraded on every build, for a stronger transmission than the one that came out.
- Torn down completely. Every unit comes apart on the bench, gets cleaned inside and out, and every part is measured.
- Every seal, every time. A full factory gasket and seal kit, including the internal seals most shops look at and reuse.
- A new torque converter. On every build. Not the old one cleaned up.
- Valve body built and tested here. Checked on a vacuum test machine so every valve moves the way it should.
- Worn parts go in the trash. Clutches that are starting to darken, a front pump that "still works", hard parts with wear. They do not go back in.
- Tested before it goes in. The finished unit is measured and tested on the bench, then installed, programmed and road-tested.
"When I build one, I only want to build it one time." Henry Tilton. Covered by our lifetime warranty.
Tell the builder about your truck
Send the year, make and model and what it is doing. You get a call back from the person who builds the transmissions.
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