Pulsating Issues with 6th gear
Thread Starter
Cruising
Joined: Aug 2008
Posts: 10
Likes: 0
From: Raleigh North Carolina
Pulsating Issues with 6th gear
I have a 98 6speed manual and when I am on the highway in 6th gear it pulsates.
It is a very regular vibration too, about 1 second of vibration, 1 second fine, 1 second vibration, 1 second fine and is continuous. It does not vibrate if I coast in neutral (so it's not a wheel weight or alignment) and it does not vibrate in 5th gear.
It does the pulsating vibration if I am in cruise or if I am not using cruise.
I had the rear diff fluid changed to see if this made any difference (i have high miles and this needed to be done anyway) and it made no difference.
What could this be? A gear going bad? Something out of balance?
It is a very regular vibration too, about 1 second of vibration, 1 second fine, 1 second vibration, 1 second fine and is continuous. It does not vibrate if I coast in neutral (so it's not a wheel weight or alignment) and it does not vibrate in 5th gear.
It does the pulsating vibration if I am in cruise or if I am not using cruise.
I had the rear diff fluid changed to see if this made any difference (i have high miles and this needed to be done anyway) and it made no difference.
What could this be? A gear going bad? Something out of balance?
Banned Scam/Spammer
Joined: Jul 2006
Posts: 2,911
Likes: 10
From: Simi Valley CA
If you drive the same speed in 5th gear as in 6th gear, and you only hear/feel it in 6th gear.. then 6th gear in the tranny is bad. I'd really make sure this is the case because if you can get it to do the same vibration, at the same speed, regardless of gear, then it's the rear end or rear bearings. (much cheaper to r/r)
Banned Scam/Spammer
Joined: Jul 2006
Posts: 2,911
Likes: 10
From: Simi Valley CA
yes, but then it would make the noise/vibration independent of the gear. (which is why I was making sure)
Thread Starter
Cruising
Joined: Aug 2008
Posts: 10
Likes: 0
From: Raleigh North Carolina
Banned Scam/Spammer
Joined: Jul 2006
Posts: 2,911
Likes: 10
From: Simi Valley CA
Sorry, tranny work is in your future. Until then, use 5th whenever possible. What ever is making noise/vibration is not getting better as you use it.
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Pro
Joined: Aug 2007
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From: ATLANTA GA
I have a 98 6speed manual and when I am on the highway in 6th gear it pulsates.
It is a very regular vibration too, about 1 second of vibration, 1 second fine, 1 second vibration, 1 second fine and is continuous. It does not vibrate if I coast in neutral (so it's not a wheel weight or alignment) and it does not vibrate in 5th gear.
It does the pulsating vibration if I am in cruise or if I am not using cruise.
I had the rear diff fluid changed to see if this made any difference (i have high miles and this needed to be done anyway) and it made no difference.
What could this be? A gear going bad? Something out of balance?
It is a very regular vibration too, about 1 second of vibration, 1 second fine, 1 second vibration, 1 second fine and is continuous. It does not vibrate if I coast in neutral (so it's not a wheel weight or alignment) and it does not vibrate in 5th gear.
It does the pulsating vibration if I am in cruise or if I am not using cruise.
I had the rear diff fluid changed to see if this made any difference (i have high miles and this needed to be done anyway) and it made no difference.
What could this be? A gear going bad? Something out of balance?
They rebuilt mine the right way after a horrible experience with a different vendor on LS1tech.com.
Another good thing is that 6th is in the VERY back of the transmission. Its possible to repair this without tearing down the entire unit, I had my 5th repaied from that other vendors mishap and it took them under a hour to do it.
Its also possible they can repair/replace your 6th gear without removing the transmission, Just by removing the differential and sliding the rear cover off. they can do it with it on the lift.
Give em a call and see what they say
