Have a Hyundai (roughly 2006) 740-7 loader. When go to 4th gear it wants to flash up a b4 fault that says slippage at clutch k4. I would assume the first place to start would be to check pressures with gauges? I do not have a manual so any help would be appreciated. Changed the transmission oil and filter and everything looked good there. Old oil looked good and problem still persists. Thanks
Maybe post a picture of the top of the control valve on the transmission, and maybe someone who has info on it can tell you where to put the gages. Simon C
Hi Oliver, I'll share a manual of a 4WG160 in a PN. B4 coming up also @low load from engine? Like shifting around idle in manual mode.
And: Does it throw code almost immediately after shift into K4 or during drive with heavy load? F. e. uphill, full bucket, high engine speed, 4th gear?
When I’m not sure if this is the control valve or not
It only comes up when it shifts into 4th gear. Most the time it will go in 4 for about 5-10 seconds and then the fault code pops up. Most the time always have half throttle or more since that’s road gear and trying to scoot down the road. It will do it on flat ground or uphill. Always in 4th gear. Never in the other 3
So I'd assume there is an issue with clutch pressure during drive, modulated pressure during shift might be ok. Check pressure port 60 (K4) in 4th gear (K3+K4), countercheck pressure K3 (58) for example in 3rd (KV+K3), then in 4th. Any difference? ports are M10x1 thread.
Make sure you clean the top off very well before removing the plugs. I generally loosen the plugs about 1 turn and then reblow with air to make sure nothing loose around the plug falls inwards. Simon C
Ok I checked pressures at idle with the machine shop temp(55 degrees F) port 58 I had 210 psi in both gear 3 &4. Port 60 I had 0 in 3 and 68psi in gear 4.
Possibly swap solenoid K4 with any other and see whether issue moves to another clutch. There is some hope, K4 solenoid is troublemaker.
Ok Thanks. I looked through that manual you sent me. Greatly appreciated by the way. I can’t find the k4 solenoid location anywhere. I’m guessing it’s in the valve block assembly where I checked pressures? Any insight would be great. Thanks
Oliver; Y1 is K4, Y2 KR, Y3 K1, Y4 K3, Y5 KV, Y6 K2. See page 44 and 45, a bit tricky and hidden. Solenoids hidden underneath both covers.
Thanks for the help on this. It ended up being the solenoid was bad. It’s going now. Thanks again