Built 4L65 whining in gear
Built 4L65 whining in gear I have a FLT Level 6 4L65E in an AWD Trailblazer SS.
I have been hearing a whining on acceleration and assumed it was the blower, but last night I noticed that the noise starts right when you drop the car in gear. For example I was in the garage just sitting still, car in park no noise, put the car in D,R,1,2 or 3 and voila, noise. Again this is all sitting still.
Anyone far smarter than me want to weigh in on what it could be? Does what I've described isolate converter? Pump? Tranny?
It runs fine with no noticeable problems. Shifts are normal.
I have been hearing a whining on acceleration and assumed it was the blower, but last night I noticed that the noise starts right when you drop the car in gear. For example I was in the garage just sitting still, car in park no noise, put the car in D,R,1,2 or 3 and voila, noise. Again this is all sitting still.
Anyone far smarter than me want to weigh in on what it could be? Does what I've described isolate converter? Pump? Tranny?
It runs fine with no noticeable problems. Shifts are normal.
Moderator
Joined: Aug 2010
Posts: 7,323
Likes: 529
From: Ann Arbor, MI
So you have the whining in 1st or Reverse gear, but not in Park/Neutral. The difference is that in 1st/Reverse the Sunshell/Reverse drum assembly is spinning. Two bushings support this assembly, plus the internal torrington bearing in the rear planetary. Any of those could cause the whine. The reverse drum turns inside the band; I don't know what sound a too-tight band would make.
Probably time to call FLT and see what they want you to do. Even if you decide to live with it, it would be good to let them know now for warranty reasons.
Probably time to call FLT and see what they want you to do. Even if you decide to live with it, it would be good to let them know now for warranty reasons.
Moderator
Joined: Aug 2010
Posts: 7,323
Likes: 529
From: Ann Arbor, MI
So you have the whining in 1st or Reverse gear, but not in Park/Neutral. The difference is that in 1st/Reverse the Sunshell/Reverse drum assembly is spinning. Two bushings support this assembly, plus the internal torrington bearing in the rear planetary. Any of those could cause the whine. The reverse drum turns inside the band; I don't know what sound a too-tight band would make.
Probably time to call FLT and see what they want you to do. Even if you decide to live with it, it would be good to let them know now for warranty reasons.
Probably time to call FLT and see what they want you to do. Even if you decide to live with it, it would be good to let them know now for warranty reasons.
