For those that have followed my build, I replaced a TH350 about 7 years ago. At the recommendation of a mechanic friend who worked where I used to store the K5, I purchased a performance built SS Mega Monster 700R4 from Monster Transmission. It's advertised to handle 650HP.
Fast forward 6 1/2 years and less than 1500 miles, and the transmission appeared to have lost the 3-4 clutch pack on the K5's maiden voyage road trip.
I placed a call to our resident transmission expert and he suggested I ship it to him. Plan was to see what was really inside the case, salvage anything worthwhile, replace and rebuild the rest. Got the report today. Upon teardown they found:
- The 1800-2000 stall converter I purchased from Monster, was really a bone stock, off the shelf 1500 stall converter and it only gets worse from there...
- "Looks like a good bit of parts were thrown at a worn out core in my observation"
- It had red clutch plates and Kolene steels, these are regarded as "race parts" in most circles, not very durable for extended street use.
- It had 4 pinion front and rear planets which is ok in my book but 5 pinion units would be more in line with a 650HP build.
- None of the bushings were replaced except the pump body and they were badly worn
- Clearences were way off
- Minimal valve body and pump mods were performed beyond those that just make the trans shift harder.
- Pump was out of alignment and had minimal prep
- Stator was worn on the bushing side
- Reverse drum was warped
- The 2-4 band was only making minimal contact.The 2-4 band was also a race type lining and is not a quality piece
- Input sprag race was badly worn on the contact surfaces (it was installed that way)
- Separator plate had been sanded with some kind of disc grinder and was warped
- The input drum and pistons were stock type
- No drum reinforcement at the shaft spline, stock cast pistons, modification of these items which is critical on a high HP unit in a heavy vehicle
- We also found the pump to have been damaged by some type of grinder used to clean up some pump pocket wear which creates huge internal leaks
- On the case itself, both dowel alignment points in the case are worn so we will be resleeving those and repairing quite a few stripped holes with heli coil inserts
With all of that said, I'm surprised the junk made it 1500 miles behind a BBC, much less a
or two. Monster can $uck it. Expensive lesson learned. But, I couldn't be happier with the analysis and detail provided by the Man and knowing that the "new" one will be more than capable.
Fast forward 6 1/2 years and less than 1500 miles, and the transmission appeared to have lost the 3-4 clutch pack on the K5's maiden voyage road trip.
I placed a call to our resident transmission expert and he suggested I ship it to him. Plan was to see what was really inside the case, salvage anything worthwhile, replace and rebuild the rest. Got the report today. Upon teardown they found:
- The 1800-2000 stall converter I purchased from Monster, was really a bone stock, off the shelf 1500 stall converter and it only gets worse from there...
- "Looks like a good bit of parts were thrown at a worn out core in my observation"
- It had red clutch plates and Kolene steels, these are regarded as "race parts" in most circles, not very durable for extended street use.
- It had 4 pinion front and rear planets which is ok in my book but 5 pinion units would be more in line with a 650HP build.
- None of the bushings were replaced except the pump body and they were badly worn
- Clearences were way off
- Minimal valve body and pump mods were performed beyond those that just make the trans shift harder.
- Pump was out of alignment and had minimal prep
- Stator was worn on the bushing side
- Reverse drum was warped
- The 2-4 band was only making minimal contact.The 2-4 band was also a race type lining and is not a quality piece
- Input sprag race was badly worn on the contact surfaces (it was installed that way)
- Separator plate had been sanded with some kind of disc grinder and was warped
- The input drum and pistons were stock type
- No drum reinforcement at the shaft spline, stock cast pistons, modification of these items which is critical on a high HP unit in a heavy vehicle
- We also found the pump to have been damaged by some type of grinder used to clean up some pump pocket wear which creates huge internal leaks
- On the case itself, both dowel alignment points in the case are worn so we will be resleeving those and repairing quite a few stripped holes with heli coil inserts
With all of that said, I'm surprised the junk made it 1500 miles behind a BBC, much less a
or two. Monster can $uck it. Expensive lesson learned. But, I couldn't be happier with the analysis and detail provided by the Man and knowing that the "new" one will be more than capable.
Last edited:
. I helped him build his barn, just re roofed his other barn. 
