C120 strikes again... Setback #5, (I think)

[BPEisenhower 685]

Hello there Horse Family! Another great fall day and time after work to get a few things done. Not so fast! Went to move the C120 and the entire steering pedestal moved enough to the left, the hood opened. No bolts on the right side and the left broke off above the bolts. No problem! Wrong!!! Too thin to weld, ok!  I got a Charger 12!  Started tearing it down and two problems. First, there's no spot for voltage regulator and gauge. Second, Charger 12 has electric PTO and have to drill out holes to run the through shaft and tap holes for the PTO linkages. So, I got the roll pins soaking and steering wheel shafts soaking so hopefully, no broken steering wheels. However, I did notice that the Charger 12 has a cigarette lighter and appears to have not been used. Choke and throttle pull cables still work and looks like plenty of good used parts. I also want opinions on what rims I should use for the AG tires on the rear. Do I use the skinny rims so the tires appear to be bigger or the 12 inch rims? I'll be fluid filling them anyways and painting them before mounting and fluid filling. Tell me what you would do, no wrong answers!!  Thank you all! BTW, I'm not dismounting the original tires from rims, I found an extra set 12 inches wide 😄

[James Wright 3]

Those pedestal bolts snapping above the threads sounds like a fatigue problem more than anything, so I'd check the Charger 12 frame for cracks before drilling for the through-shaft and PTO linkage — tapping into thin cast can go badly fast. On the rims, I'd lean toward the wider 12-inch set for stability with fluid fill, even if the skinny rims make the AG tires look taller. Taller sidewall does look better, though. Given the Michigan fall, at least the soaking is happening indoors.

[BPEisenhower 685]

1 hour ago, James Wright said:

Those pedestal bolts snapping above the threads sounds like a fatigue problem more than anything, so I'd check the Charger 12 frame for cracks before drilling for the through-shaft and PTO linkage — tapping into thin cast can go badly fast. On the rims, I'd lean toward the wider 12-inch set for stability with fluid fill, even if the skinny rims make the AG tires look taller. Taller sidewall does look better, though. Given the Michigan fall, at least the soaking is happening indoors.

Got plenty of nickel rod in case of a crack in the cast but I absolutely don't want to damage a good piece of it. I could use a torch but, I have patience for now 😁. I also soaked the rear hubs so I have a better chance for saving them just in case but, I want to use them for a pattern when I get the nerve to install a tall skinny set of duals instead of using threaded rods. Much better if those are solid to the axle. I've found years of neglect in maintaining equipment but never had a steering pedestal broken off on anything before. But, it's a good way to learn what to look for and how to fix. The other problem is that I was driving the Charger 12 and it began to lunge ahead and bucking violently. I'm thinking it needs fluid change and flushed before I use it again. Can't do any harm to grab a new 1410 filter and 10-30. If I remember correctly the Sunstrand is piston to piston so might be a chore to overhaul but, it doesn't scare me. Have to see if it's possible to install an oil cooler for longevity. Rather deal with hydraulic problems than electrical any day!

[pfrederi 21,216]

11 hours ago, BPEisenhower said:

Got plenty of nickel rod in case of a crack in the cast but I absolutely don't want to damage a good piece of it. I could use a torch but, I have patience for now 😁. I also soaked the rear hubs so I have a better chance for saving them just in case but, I want to use them for a pattern when I get the nerve to install a tall skinny set of duals instead of using threaded rods. Much better if those are solid to the axle. I've found years of neglect in maintaining equipment but never had a steering pedestal broken off on anything before. But, it's a good way to learn what to look for and how to fix. The other problem is that I was driving the Charger 12 and it began to lunge ahead and bucking violently. I'm thinking it needs fluid change and flushed before I use it again. Can't do any harm to grab a new 1410 filter and 10-30. If I remember correctly the Sunstrand is piston to piston so might be a chore to overhaul but, it doesn't scare me. Have to see if it's possible to install an oil cooler for longevity. Rather deal with hydraulic problems than electrical any day!

  Charger 12 had Hydro gear Sunstrands....also originally used ATF

 

Maybe yours was swapped out at some point???

[BPEisenhower 685]

On 10/27/2026 at 6:53 AM, pfrederi said:

  Charger 12 had Hydro gear Sunstrands....also originally used ATF

 

Maybe yours was swapped out at some point???

My mistake, I was referring to the C120. Still has the sticker indicating 10W30 and the Charger 12 both say ATF. Would like to know if it's Dex Merc or type F

[Bar Nuthin 3,350]

1 hour ago, BPEisenhower said:

My mistake, I was referring to the C120. Still has the sticker indicating 10W30 and the Charger 12 both say ATF. Would like to know if it's Dex Merc or type F

if the transaxle has been drained and new filter, I believe you can go with either Dex/Merc or Type F and be fine. Maybe schedule your next change out a little sooner than normal just for peace of mind.

I run Dex/Merc in my 16-Auto based on a recommendation I got from someone here.

If wanted to do a thorough flush, you could convert over to 10W30. Opinions vary on all 3.

[pfrederi 21,216]

Stick with whatever is in the tranny.  Flushing wastes a lot of time and fluid.  There is no noticeable performance difference Motor oil verses Dex/Merc ATF

[953 nut 69,787]

12 hours ago, BPEisenhower said:

My mistake, I was referring to the C120. Still has the sticker indicating 10W30 and the Charger 12 both say ATF. Would like to know if it's Dex Merc or type F

I have always heard that Type F is better for racing applications because it has no friction modifiers and less slippage but I'm not sure that it would be an advantage in a Sundstrand since it hasn't got clutches like an automotive transmission. Dex Merc is good old Dexron which is what Sundstrands left the factory with, that having been said I had a few quarte of type F on the shelf and used them in the GT-14 with no issues.

Mike @squonk has posted in the past that 10-W-40 improved the performance on his Sundstrand, he may be able to add to this question.

[squonk 48,210]

I use Mobil 1 10W-40 in my C-160 piston piston Sundstrand. I had a lurching / bucking issue shortly after I got it about 15 yrs. ago. I had to replace the hydro motor half of the trans. The pump is a bit tired. On hot days I ran an oil temp check and it got up to 160° The heavier weight oil improved performance on hills after it got hot.