In maintaining our commitment to transparency and full disclosure of everything we do, we have some pretty impressive extreme testing results to share. We also want all of our current and potential customers to always have all the data needed to make a well informed and educated decision regarding our products.
Ok, so now for the goods...As some of you already know, Jimmie Johnson's PD transmission had a catastrophic failure due to a failed input shaft. Under most circumstances this would be considered a huge set-back and cause for panic but it's quite the contrary. Jimmie was one of our very first Beta Testers to get online so we all agreed to turn him loose to see just how much real-world abuse these new clutches could take before failing. Since we already knew the failure mode of the transmission under extreme loaded conditions, albeit in a controlled environment, we were excited to see just how far this thing could go under some pretty extreme rubber-to-road abuse.
Here are the extreme testing parameters/conditions...
1) No aux ATF cooler (stock system with heat exchanger)
2) Low Viscosity ATF (reduced lubricity and thermal rejection capacity)
3) ATF temps reported at 300F
4) Over 2000 miles of hard launching/brake boosting at 17psi
5) 275 MT ET Street R radials
6) Motiv900 ST
7) Estimated power levels ranging from 650whp to 800whp
While we have determined the root cause of this failure to be due to extreme thermal fatigue of the input shaft, it's extremely important for everyone to understand and be aware of the intent and limitations of this upgrade. This upgrade is not intended for extreme racing conditions nor is it to be considered a complete, silver bullet transmission solution. This upgrade/solution simply addresses the immediately obvious design flaws in the transmission, which everyone knows to be the clutches and bushings.
Now that the clutches are providing significantly more clamping capacity, the stresses are now transferred into other areas of the transmission, or the next weakest link. In this case, it's the input shaft. So, given these results, we are extremely pleased with the performance of the clutches we have provided. Even with ATF temps in the 300F range and 2,000 miles of brake boosted launches with the worst possible ATF for the application and no auxiliary cooling ability, the clutches still had enough clamping capacity to snap the input shaft. That's pretty impressive in our opinion. Bottom line is, these clutches are tough as hell.
Here is a quote from Jimmie himself regarding the failure...
"I was just thinking the other day, almost 2000 miles of launches/brake boosting at 17#, using the factory heat exchanger, low viscosity ATF and temps reaching 300° finally causing the input shaft to snap. It's disappointing to break things, but it's actually impressive considering what it handled for so long AND it was a factory part that failed, not your upgrade. So just keep that in mind and pat yourself on the back for coming up with a set of clutches that work extremely well. People need to understand just how much we trashed that thing and how long it kept chugging along until a factory part broke. It's unreasonable to think parts won't break, but it's important what it can handle before it will break."
Attached are some of the tear-down pics from the failure mode analysis. It's easy to see to see that even though the clutches are absolutely torched, they still performed as intended.
Ok, so now for the goods...As some of you already know, Jimmie Johnson's PD transmission had a catastrophic failure due to a failed input shaft. Under most circumstances this would be considered a huge set-back and cause for panic but it's quite the contrary. Jimmie was one of our very first Beta Testers to get online so we all agreed to turn him loose to see just how much real-world abuse these new clutches could take before failing. Since we already knew the failure mode of the transmission under extreme loaded conditions, albeit in a controlled environment, we were excited to see just how far this thing could go under some pretty extreme rubber-to-road abuse.
Here are the extreme testing parameters/conditions...
1) No aux ATF cooler (stock system with heat exchanger)
2) Low Viscosity ATF (reduced lubricity and thermal rejection capacity)
3) ATF temps reported at 300F
4) Over 2000 miles of hard launching/brake boosting at 17psi
5) 275 MT ET Street R radials
6) Motiv900 ST
7) Estimated power levels ranging from 650whp to 800whp
While we have determined the root cause of this failure to be due to extreme thermal fatigue of the input shaft, it's extremely important for everyone to understand and be aware of the intent and limitations of this upgrade. This upgrade is not intended for extreme racing conditions nor is it to be considered a complete, silver bullet transmission solution. This upgrade/solution simply addresses the immediately obvious design flaws in the transmission, which everyone knows to be the clutches and bushings.
Now that the clutches are providing significantly more clamping capacity, the stresses are now transferred into other areas of the transmission, or the next weakest link. In this case, it's the input shaft. So, given these results, we are extremely pleased with the performance of the clutches we have provided. Even with ATF temps in the 300F range and 2,000 miles of brake boosted launches with the worst possible ATF for the application and no auxiliary cooling ability, the clutches still had enough clamping capacity to snap the input shaft. That's pretty impressive in our opinion. Bottom line is, these clutches are tough as hell.
Here is a quote from Jimmie himself regarding the failure...
"I was just thinking the other day, almost 2000 miles of launches/brake boosting at 17#, using the factory heat exchanger, low viscosity ATF and temps reaching 300° finally causing the input shaft to snap. It's disappointing to break things, but it's actually impressive considering what it handled for so long AND it was a factory part that failed, not your upgrade. So just keep that in mind and pat yourself on the back for coming up with a set of clutches that work extremely well. People need to understand just how much we trashed that thing and how long it kept chugging along until a factory part broke. It's unreasonable to think parts won't break, but it's important what it can handle before it will break."
Attached are some of the tear-down pics from the failure mode analysis. It's easy to see to see that even though the clutches are absolutely torched, they still performed as intended.
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