Hello, I have an 8000 hour 432E which drives perfectly until the tranny gets warm. It then won’t select first or 4th gear in forward range. All rear gears are fine and the transmission is generally strong. We have changed the solenoids/ coils on the transmission and the valve on the top of the transmission, but no change to our missing gears. Anyone had any experience with this problem? Thanks or your advice.
Sounds like internal leakage in a clutch when the oil is warm. The common factor to 1st & 4th speed forward is the Forward Low clutch. The Forward High clutch is used for 2nd, 3rd, & 5th speeds in the forward direction. What oil are you using in it..? Have you tried pulling the transmission magnetic screen and/or filter to see if there are clutch particles in it..?
Thanks Nige for your input. We changed the oil etc and found no mischief at all. It has full power when cold in all gears, but when it gets warm, after moving out of either of these gears, 1F and 4F won't select again at all. It still feels very much like an electrical fault but no fault codes show on the dash. Might have to get a Cat tech out with his computer. This backhoe has only 4 speeds forward and reverse, power shift or fully auto option.
Try swapping the solenoids for the Low & high clutches and see if the problem moves to 2nd & 3rd...?
Hi! I have the same problem. Did you manage to solve it? What was the problem?
We did not solve it. 8 years and we still drive in 2nd and third gear. We did a lot of tests and all looks good. So next step might be to pull transmission apart but when do we have time!
Thank you so much for the answer!
Welcome to HEF, Konst ! Oldboy; You mentioned that you were going to have a Caterpillar tech look at it. Did that ever happen ?