cutlassman Posted August 26, 2010 Report Share Posted August 26, 2010 Hopefully this is an easy fix. After my engine rebuild ('92 Vert, 3.1L), the transmission clunks when going from park to reverse and has a quite noticable, hard, downshift clunk from 2-1. I thought at first this was from sitting for a few months, but that's not the case. It shifts fine otherwise. Fluid level and quality is fine and there's only ~2,000 miles since fluid/filter change. I'm guessing this is a vacuum issue, but I admit I don't know the trans set-up well and the manual doesn't offer much help. Any ideas on cause(s) and details on where to look in the engine compartment is appreciated. I'm guessing a vacuum line may be bad (knocked off, not replaced during the rebuild), but I don't know exactly where to look. Quote Link to comment Share on other sites More sharing options...
Highmilagecutlass Posted August 27, 2010 Report Share Posted August 27, 2010 Okay Here's my theory. I had a similar problem with my cutlass when the lower motor mount tore it's self apart. It was the one directly below the harmonic balancer. It's a fluid filled mount to absorb the vibration. I at first noticed the clunk going into reverse and then I replaced the dog bones, and the the clunk improved but not completely. A good friend of mine thats a mechanic rode with me once and said hey your mount is bad..and he was right..I replaced the mount and the clunk and vibration went away. I think that I bought the new motor mount from Auto Zone.. Pop the hood and have a friend apply the brake with the car idling then shift the car to reverse and watch the engine move. Is it a smooth transition ? or a violent jerk ? Just make sure that the parking brake or your helper has both feet planted on the brake pedal before attempting this test. Quote Link to comment Share on other sites More sharing options...
alec_b Posted August 27, 2010 Report Share Posted August 27, 2010 I'd second the motor mount. My regal does that when going from reverse to drive and when downshifting on occasion, and I know my front mount is shot. Quote Link to comment Share on other sites More sharing options...
cutlassman Posted September 8, 2010 Author Report Share Posted September 8, 2010 I took a short video of the clunk and will try to post here. This is after starting the car cold, shifting to reverse from park. The lower motor mount sounds like the culprit. The two dog bone mounts up top are in great shape - replaced a couple years ago. About the lower motor mount...what's the procedure to change that out with a new mount? I know when rotating the engine forward, the trans should be in neutral. When I did the engine rebuild, the trans was in park and I had the engine rotated forward for quite a while. Think that might have been the problem and the reason the clunk is showing up now? Worn out mount? Seems like a simple enough fix, but I can't find much on swapping out that lower motor mount. [video=youtube;ABnBr7_NW_Y] Quote Link to comment Share on other sites More sharing options...
Highmilagecutlass Posted September 10, 2010 Report Share Posted September 10, 2010 Its a fluid filled mount could have been torn while you were working on it. I bought mine at Autozone and they have a life time warrenty even though it's an imported from china or mexico. 5 bolts hold it place and you can swap it out by removing the mounting bolts and lifting the engine with a block of wood under the oil pan or with a engine support brace or cherry picker, only lifting just enough to get the mount to clear. Use a spotter to watch for things hitting or things being stretched to far. Spend $20.00 and buy a chilton or a haynes repair manual..money well spent. And disconnecting the battery before attempting this would be smart.. Good Luck Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted September 10, 2010 Report Share Posted September 10, 2010 jeez, that's rough! i blew the lower mount on the MC a few years ago, but damn have i never saw that kind of movement. Quote Link to comment Share on other sites More sharing options...
cutlassman Posted December 14, 2010 Author Report Share Posted December 14, 2010 I just wanted to follow-up for anyone that comes across this post and has the same problem. Thanks for the replies - you guys were right. I finally got around to replacing the lower engine mount. You can see the OE fluid-filled mount on the car was completely trashed. I went with the fluid-filled replacement. Raising the engine enough to get the old mount out and new one in is a PITA. I had to loosen the heater hose that runs along the passenger's side wheel well because it was stretching too much. Getting the engine bracket back over the new mount bolts was a serious challenge. Box end wrenches are a must for the top two nuts on the mount. The end result is perfect! The nasty clunk is gone and the shift to reverse from park is nice and soft! Now, on to the next project... Quote Link to comment Share on other sites More sharing options...
GOT2B GM Posted December 15, 2010 Report Share Posted December 15, 2010 Nice work Quote Link to comment Share on other sites More sharing options...
rich_e777 Posted December 27, 2010 Report Share Posted December 27, 2010 You got off easy my `94 Cutlass still has that same noise when changing gears and accelerating after coming to an almost or complete stop. Changed all the mounts, tightned them down and still hearing that noise. I think mine has something to do with the exhaust system, somebody jacked my catalytic converter a few years back, cut it out real nasty looking and the fucktard i paid $300 to replace it probably did a shit job on it because that when i started noticing the noise on my car, for $300 fucking bucks i should have dual side exiting pipes like on the oldschool shelby cobras. Quote Link to comment Share on other sites More sharing options...
thikstik Posted January 3, 2011 Report Share Posted January 3, 2011 You got off easy my `94 Cutlass still has that same noise when changing gears and accelerating after coming to an almost or complete stop. Changed all the mounts, tightned them down and still hearing that noise. I think mine has something to do with the exhaust system, somebody jacked my catalytic converter a few years back, cut it out real nasty looking and the fucktard i paid $300 to replace it probably did a shit job on it because that when i started noticing the noise on my car, for $300 fucking bucks i should have dual side exiting pipes like on the oldschool shelby cobras. That sucks, when i was 16, a retard lifted my 71 Lemans ON THE HEADER. Yes lifted car with that front weight on a header. Needless to say it ruined it and i got nothing. The after hot rodding my 75 Gremlin X coming home from the exh shop with true duels and a new engine, I pop in to the Omega tirs shop. Fools who didnt speek English jacked it on , guess what , the header! It ws leaking after 2 minutes of idleing so it was hard to argue. So a $450 header that had to be modified for another$100 was messed up. I got $200 cause the judge wouldnt know how to fill his bmw with gas. Quote Link to comment Share on other sites More sharing options...
thikstik Posted January 3, 2011 Report Share Posted January 3, 2011 That sucks, when i was 16, a retard lifted my 71 Lemans ON THE HEADER. Yes lifted car with that front weight on a header. Needless to say it ruined it and i got nothing. The after hot rodding my 75 Gremlin X coming home from the exh shop with true duels and a new engine, I pop in to the Omega tirs shop. Fools who didnt speek English jacked it on , guess what , the header! It ws leaking after 2 minutes of idleing so it was hard to argue. So a $450 header that had to be modified for another$100 was messed up. I got $200 cause the judge wouldnt know how to fill his bmw with gas. Everytime i post, it adds the previous quote!! why!! Quote Link to comment Share on other sites More sharing options...
thikstik Posted January 3, 2011 Report Share Posted January 3, 2011 Everytime i post, it adds the previous quote!! why!! see Quote Link to comment Share on other sites More sharing options...
thikstik Posted January 3, 2011 Report Share Posted January 3, 2011 see see,see senior Quote Link to comment Share on other sites More sharing options...
AL Posted January 3, 2011 Report Share Posted January 3, 2011 Are you hitting reply to thread on the bottom left or are you hitting reply under the last post? Quote Link to comment Share on other sites More sharing options...
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