Engine/Transmission (1994 - 1998) 47RH problems

[ndurbin]

I've been noticing some problems lately with my transmission. If I am turning from a stop about mid-way thru the turn it sounds/feels like the TC is locking up. But it unlocks before the turn is done. It's either the TC is locking up or it trys to shift into 2nd or 3rd to soon, don't really know for sure. Also when the TC locks up it doesn't seem to be as firm (usto make the truck shudder abit when it locked up). And yet another thing I have noticed is when in Drive it starts out in 3rd unless I really get after it. It's also a real slug in the mornings, I let it idle in neutral for a few min. before I take off but that doesn't seem to make much difference. Once it finally gets warm it does fine. But with these cooler temps now it takes 10-20 min of driving before it acts like it should.



TPS is new and is re-wired. Also has a new stock trans. temp. sensor. The check ball in the line ahs been removed.



Could I have a bad solenoid or something forcing these weird problems? Or maybe do I have a bad valve body?



I don't have much faith in calling Blumenthals and tlaking to them about it. Their automatic transmission customer service is alil lacking.



TIA

Nathan

 

[Cummins4Life]

Sounds like the shift points are screwey, theres an adjustment on the drivers side of the valve body to make it shift later during light throttle, 1turn=75rpm later. I cant remember what causes 3rd gear starts. Is the OD switch on the dash in good shape? Any corrosion around the connectors on the transmission and xfer case? Dunno why it would try to lockup around a corner.



Call some of the bigger transmission vendors and bug them, I know DTT and Dunrite are willing to help over the phone.

 

[Joe G.]

You might be low on ATF.

 

[ndurbin]

I checked the ATF level. It was a smidge low. Went out and drove it around again. That seemed to cure the problem when turning and alil of the sluggishness.



It still takes off in 3rd unless I get after it and lock-up is still soft.



I didn't get the chance to call any of the big transmission builders. Get to that tomorrow.



Nathan

 

[Joe G.]

Make sure that you check the AFT with a warm transmission with the shifter in N. You may have low line pressure or the kick down cable is too loose.

 

[ndurbin]

It was as warm as I could get it w/o covering the radiator up. Which was only about 100-115* since it's in the low 40s upper 30s here.

 

[JPittinger]

I had some similar problems, but mine occured when it got hot in stop and go traffic. I finally just put test gauges on the ports and compared the values to the ATSG book. Ended up being a sticky throttle valve in the valve body. I rebuilt the whole transmission with Goerend parts, put in a rebuilt valve body, and now it kicks @$$. Get the book and you'll see the 47RH (H=hydraulic) is pretty easy to diagnose.

-JJ