Possible bad convertor

Hey all, got something weird going on. Went to a mud race today and after my son made his first pass, I knew something was up. Usually when we launch we start off in 2nd gear foot brake to 35/3800 rpm the truck starts to pull and we launch. Today foot brake and easily stall to 45/4800 rpm. Our ET was off by .5 average for the six passes we made. Trans itself, c6 seemed to be fine. Was acting as if we were walking through the convertor. Shift light usually comes on just before finish line- 200 ft. Came on today at about 150 ft. When we got home checked fluid in trans. Full and still a light pink/red color. But had a slight burnt smell. The convertor is a FTI mud racing 4000 stall spragless unit. The trans is a c6 built to frank Merkel specs. And a Broader reverse manual valve body. The combo has been flawless for the last 3 seasons. Any info much appreciated, never had a convertor fail so not sure if my thinking is correct. Thanks cory

Convertor beginning to slip or loosen up. How old is the convertor?

The convertor is 5 yrs old. Probably has about 100 passes on it.

Sounds familiar to what happened to me a few years ago twice when I had 7 in the drum.
I had a steel plate break that allowed the frictions to slip. You know the clutch pack has steels between the frictions. They are also called clutch plates or lock rings. There is a newer friction material that will let you go to 5 instead of 7 where the plate thickness goes up including the plate strength. I think Broader carries the new clutch packs.

All the clutches and steels, direct billet piston, servo and lever, 5 clutch hi drum and valve body all came from Broader. Going to drop the pan this weekend and see what the filter looks like. If there is debris, I will yank the transmission out and tear it down. Been thinking probably forward clutch. It takes a beating. We launch in 2nd gear. Thanks cory

Dropped the pan this weekend, didn't find any clutch material, but did find metal shaving, and a little copper. We also have a external filter on the cooling circuit. Cut it and found very fine metal shavings in it as well. Guessing a planetary and or bearing in convertor. Thanks cory

Isnt mud racing a bit too much extended run time for a spragless converter? Ive had great success with mechanical diode converters but I'm bracket racing an 1/8th or a 1/4 mile under 9 seconds at a time.

We go 200 ft in about 3.7-3.9 seconds, doubt that length of time is a problem. Thanks cory

2 wicked wrote:Hey all, got something weird going on. Went to a mud race today and after my son made his first pass, I knew something was up. Usually when we launch we start off in 2nd gear foot brake to 35/3800 rpm the truck starts to pull and we launch. Today foot brake and easily stall to 45/4800 rpm. Our ET was off by .5 average for the six passes we made. Trans itself, c6 seemed to be fine. Was acting as if we were walking through the convertor. Shift light usually comes on just before finish line- 200 ft. Came on today at about 150 ft. When we got home checked fluid in trans. Full and still a light pink/red color. But had a slight burnt smell. The convertor is a FTI mud racing 4000 stall spragless unit. The trans is a c6 built to frank Merkel specs. And a Broader reverse manual valve body. The combo has been flawless for the last 3 seasons. Any info much appreciated, never had a convertor fail so not sure if my thinking is correct. Thanks cory

Did you get a chance to flash the convertor in any other gears to see if it made any difference in the stall speed?

I think I would go through the trans while it's out, and go from there. It won't hurt to clean/inspect it even if you don't find anything wrong since you have mental in the system and just for peace of mind.

Hey all, got the trans apart today, found forward planetary was the cause of the metal in the pan. The gears and bearings are fine, but were the planetary gear set goes through the hub it was gauled up on the hub. Rear planetary looked brand new. Low clutch pack was perfect, forward clutch looked good. But direct clutch is just starting go bad. Steels were discolored and clutches starting to get blackened. Pump looked perfect, like new. Going to order a wide ratio gear set, new seals, TB valve body, clutches, and R servo and E lever. And send the convertor back for a freshen up and restall. Thanks cory

2 wicked wrote:Hey all, got the trans apart today, found forward planetary was the cause of the metal in the pan. The gears and bearings are fine, but were the planetary gear set goes through the hub it was gauled up on the hub. Rear planetary looked brand new. Low clutch pack was perfect, forward clutch looked good. But direct clutch is just starting go bad. Steels were discolored and clutches starting to get blackened. Pump looked perfect, like new. Going to order a wide ratio gear set, new seals, TB valve body, clutches, and R servo and E lever. And send the convertor back for a freshen up and restall. Thanks cory

R Servo: If you missed it on Those. If you are getting the other brand good. I bumped this thread for another new member having C6 Troubles. If you already knew cool.

https://www.429-460.com/t26334-c6-shifting-hard-into-high-gear