All,

Does anyone have numbers/experience on the life expectancy of a transmission for the Gen 3? I've heard 40 hours. Erik called foul on my numbers in an email, but hasn't produced anything to back that up. Does anyone have any relevant numbers/data on this subject?

Andrew

I was told by an independent SRF transmission builder to expect 40 hours if you run ATF. It was suggested that you might get significantly more if you used 75-90 gear oil, but that would cost you a bit of horse power due to additional drag (how much I don't know).

I also was told that 3 and 4th gears could probably be sourced elsewhere at some additional cost that might last longer, but this is clearly an Enterprise task.

I changed over to 75-80 in my Gen3 since I don't have any SCCA racing plans till spring, only track days, so please no comments about this oil being legal of not as I don't really give a RA at this time.

I am not sure how 40 hours equates to on track time but here is my story:

This year I ran 8 double race weekends (16 races) with test days in every event but 1. In addition to those days I ran a test day in January, 2 days at an official SCCA tire test with 5? different drivers in my car, and 1 day at an unofficial GY tire test. So call it 28 days on track this year? I would say that exceeds 40 hours, easy.

OH and I am inept at heel toeing, so I just skip that altogether.

Here's to jinxing myself.

-Mike

Edit: poor math, fixed it

MikeMiz11 wrote:
... OH and I am inept at heel toeing, so I just skip that altogether.

Here's to jinxing myself.

-Mike

I don't think the downshifts would be much different than before.

I PUT 87 HOURS ON MY NEW GEN 3 TRANSMISSION BEFORE IT LOCKED UP IN 5 TH GEAR

It's good to see some data that supports a longer transmission life.

Mark Wendling had a trans failure at the SP Labor Day races. Believe the trans had 5-6 races after the rebuild for gen3 conversion but he needs to verify that figure.

I used a 50/50 fill of ATF and 75/90 gear oil, but I had a very short season unrelated to the car (less than 5 hours of racing) so I have no useful data. But in the offseason I think I'm going to switch to a 100% synthetic gear oil. I would think the HP drag would be minimal once the fluid gets warm.

With the extra abuse from the SRF are most running oil, or are they still using ATF

Dave Skinner say to use 75-90 gear oil in GEN3 transmissions, since he builds a lot of transmissions I listen to him.