Hie all Have an issue on my cat 424D with RXA serial number It's a 2x4 1st and 2nd gear issues While machine is lifted up If put on 1st gear tyres spin but very slow Upon acceleration no change 2nd gear tyres also spin very slow but upon acceleration there is just a little increase in speed.. 3rd gear spins normal and upon acceleration there is increase in speed 4th gear spins normal and upon acceleration there is increase in speed When machine is on the ground 1st gear machine does not move when accelerating 2nd gear I'm able to move it but very slow and there is no increase in speed when accelerating 3rd and 4th respond ok ... Diagnostics done "- Replaced transmission filter Cleaned strainer Replaced transmission oil Strainer did not have any shavings just a little dirt that looked like grease Filter was clean when cut Even after replacing oil and filter issue still persists (Machine had damaged the hydraulic pump shaft seal and the hydraulic oil had slipped into the transmission before...)
Any Fault codes? Park brake disengaging completely? Previous oil look dark or smell burned? Does the engine sound like its loading when trying to travel? By your description, it sounds like you have an oil pressure bypass happening.
Attached the SysOp for the transmission. What oil did you put in the transmission.?
* Unable to get fault codes * Park brake disengages fully * Previous oil was reddish but looked thicker as mentioned that the hydraulic oil slipped into the transmission because of the damaged hydraulic shaft seal * Engine sound normal
* Thanks for the document * I put in sae-30 which the dealer recommended.. But previous owner seemed to have used atf oil from what he explained