GMC Repair: 1996 GMC differential whine and drive line slap., gmc yukon, transmission problems

Question
I have a 1996 GMC Yukon and while accelerating moderatley, I get a slight to moderate "slap" that is heard and felt when the tranny shifts from 1st to 2nd. Also, I seem to have a slight diff whine only while accelerating. The whine changes pitch and volume with higher speeds. The whine is not present while coasting with my foot compeletely off the accelerator. Do I have two seperate problems? What is causing the "slap"? What seems to be the issue with the diff?

Answer
Without hearing these noises, They could be anythin from bearings in the differential or in the axles to baerings and or a transfer case chain if this is a 4x4 or AWD vehicle to transmission problems

You need to have a professional LISTEN to these noises..


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