Hello guys. I have a 950F series II wheel loader that is losing power momentarily while moving. To explain the issue more, it does not matter what gear the transmission is in, but when you start driving the loader it will be moving fine, and then randomly it seems to bog the engine right down to almost a stall for about 5 seconds, and then it picks up power and keeps moving like normal, until about every 30 to 60 seconds, and then it does it again. It does this more frequently when in 3rd or 4th gear then 2nd or 1st, but it does still happen in 2nd and 1st. It also is making the transmission oil heat up much faster then normal. So far I have changed the fuel filters, transmission filter, and engine air filters to see if it would make any difference or not, but it did not help. I also cut open the transmission filter, and I did not find any abnormal/large filings or clutch disc material in the filter. The transmission oil also does not smell burn't. Second thing I did was look into the transmission pump, I took everything apart and the pump appeared to be in good condition other then the bearings/bushings had a bit of wear on them, but not serious enough to cause a problem. I put in a new transmission pump anyways though and resealed everything so that there was no leaks, but it still made no difference. Now I am kind of thinking that unfortunately I am having torque converter issues, but I find it odd that I didn't find any evidence of this in the filter, BUT, I did find a yellow substance in the transmission filter that looks like Cat yellow paint, which I'm not sure how it got in there. The loader was repainted shortly before I bought it, so I assumed maybe some paint got in there somehow. I also noticed this substance though in the torque converter housing when I took the transmission pump off though as well. I took some pictures of the filter and housing for you to see. The filter also was quite dirty, but I never had any issues before the power loss started to happen, and supposedly this filter has less then 100 hours on it because the place it was purchased from had changed the transmission oil and filter (BS). I'm not sure were I should head next with this problem. I'm thinking that I am going to have to look into getting a set of gauges and doing some pressure testing, but I am still unsure of why if the torque converter is going out that there would be no evidence of this in the filter? Seems like something simple may be wrong but I am just missing it. Thanks alot guys. To add, it is a 1994 model year, serial number 8TK01217.
Did you clean this screen and replace the seals? #3 & 5 seals. #10 screen
Took the filter apart, there was a little bit of sediment right at the bottom of the filter but other then that it was clean. For sure not enough to cause any issues.