Propulsive Dynamics ZF6HP19/21 upgraded transmission bushings information
Late last month Propulsive Dynamics announced on BimmerBoost that they are working on hardware upgrade solutions for the ZF 6HP19 and 6HP21 transmissions. Part of their upgraded performance transmission hardware includes upgraded bushings.
Why are upgraded bushings important?
1. The spiraled oil groove in the support bushings increases lubrication and cooling for the internal shafts which increases durability and longevity in the trans.
2. The upgraded metallurgy eliminates the pressure bleed in the dynamic (shifting) clutches. This is the most critical countermeasure because it's one of the main reasons the E Clutch (4-5-6) is slipping at the higher power levels. Because of this, we really don't know the true capacity of the stock trans.
3. The pure aluminum casing acts as a thermally activated locking mechanism which keeps the bushing axially aligned to the shaft's axis. This improves the true position, circularity and concentrically of the shaft to bushing relationship. Again, increasing durability and longevity.
The bushings are a major performance component and a very important area in the transmission design especially as it pertains to capacity and longevity upgrades.
More details on Propulsive Dynamics ZF 6HP19 and 6HP21 upgrades will come soon.