there's a lot of vibration in my transmission from 40 to 60mph im pretty sure its a rear wheel bearing. the haynes manual doesn't really go into detail on the process so what all do i have to take off to get to the rear wheel bearings?

 

First off, what year and trim is your car and does it have drums or discs. Second why would you think wheel bearing if the transmission is vibrating?

 

does it stop after 60? It might be your u joints. when I got my car it vibrated past 25 under throttle but would stop when I left off the gas. both front and rear were really broke though. they were about to completely fail.

does it do it in any perticular gear. think of all your simptoms. I doubt its wheel bearings.

 

hey sorry didnt want to start a new forum so if its possible you think you can still post on how to get the back bearings off because thats what i need to do with my car and i dont want to take it apart without knowing first what i need to do and what i need for the job. fyi i have drums in the back of mine and its a 84 gs. thanks
p.s. it sounds like you need to take a look at your transmission, gears, or maybe somthing might be loose in there.

 

you should find the link to the FSM. it will save your life.

 

more info on the car is needed. you should check the front and rear u-joints before you go tearing into teh wheel bearings. the wheel bearings will make a growling noise when they are bad and the sound is very distinctive coming from the rear. trans vibration can be cause by a few things. first, a bad trans mount, bad engien mount(s) or a bad u-joins(s).

 

awhile back i put the car on jack stands and went through the gears and the vibration was still there and when i stopped and just put the car in first and got out the drivers side rear wheel was spinning but the passenger side seemed to stick. so will i be able to visually tell if the u joints are bad and where can i get new ones for cheap?

 

Bearings usually make noise when they are bad, not vibrate. I'm in with the others, check out that driveshaft/u-joints or trans mount.

 

+1 on looking at the driveshaft U joints. I don`t know how many shafts I have replaced over the years on 2 1st gen cars I own here. I always get a used one from someone as new shafts are REALLY expensive. Most of the time, the joint will seize one way or the other or be extremely hard to move back & forth. Pretty easy to spot but you need to take the shaft loose from the car to do this.

 

any idea how much new u-joints are gonna cost? can i get those at autozone?

 

From what I understand, you won`t be able to put new joints in. The ones that are on the ends of the shaft now, are pressed in & non removable. I did have the last shaft rebuilt at a company here in town & they put in replaceable joints but had to cut the old joints off & weld in the new ones. Ran me about a 100 if I remember right. I could have gotten a used one from someone for 50.

 

79-80 RX-7's have replaceable u-joints. 81-85 require replacement of the driveshaft.

 

Well that right there, explains why I have never been able to replace mine. I have an 83 & 85! LOL!

 

ok so who sells new Rx7 drive shafts and how much is that gonna cost? could i put new u-joints on a 79 or 80 shaft and use that?

 

www.mazdatrix.com

 

sweet! the after market shaft from mazdatrix is $267 (which is more than i can afford right now) but you can take the joints off of it so if they ever go bad again you can just rebuild them.

 

the mazdatrix driveshaft is really nice from what i've heard. i bought a drivshaft from another member that was only a few months old. yo umay want to go that route. before you do though, confirm if the u-joints are worn or if they're still good.

 

yeah the haynes manual basically says to check for excessive play

 

What year car are you having the trouble with? Something else you need to make sure that you get right is the mating flange on the rear of the shaft. I did once get a used shaft from someone & had to replace the flange on the stump to get the bolt pattern to line up. Just a thought.

 

its an 83. thanks for the heads up but i think im gonna save up and get the one from mazdatrix. so any body know what might happen if i keep driving with the bad joints?

 

Well, vibrations in the drivetrain can`t be good for the transmission or stump. I`m not going to tell you that the back end is going to explode or the transmission will fall out & you will see it behind you on the road in the rearview, but bearings & out of balance conditions of the components attached to them, don`t help their lifespan much. A little off the subject but did lose a pilot bearing once & then the tranny started having vibrations which didn`t take long for the input shaft bearings to the front of the transmission to go bad. Was a mess. Ended up having to replace the transmission with another. $5 bearings cost me $225 later. If I hadn`t have done the work myself, would have been a LOT more.

Bottom line, I really don`t think I would want to drive around long with my driveshaft out of balance. You MAY end up later, having to repair something else. Your call.

 

They can be replaced. I have had it done on my 85. There are threads on how to do it along with the replacement u-joint part#.

 

My 85 was also redone. The company that did it put in Dodge truck U joints if I remember right. Have the paperwork around here somewhere. The new joints even had the grease fittings on them which was nice. The most work they had to do was cutting off the old ones & welding the new ones on. If there is another way to do it, may look into it myself to see what needs to be done.

 

I had that method done also... I am talking about replacing the "non-replaceable" ujoint without welding a new end on the shaft. There is a way to punch out the supposedly non-replaceable ujoints and put in new ones.

 

You may also want to check the tail shaft bushing for play. Try to move the drive shaft from side to side while it is installed in the transmission, there should not be allot of movement. This should be repaired as well if it is bad. Not an expensive part but you have to pull the tail shaft housing to install the new bushing.

Obviously there is a repair for the later shafts because that is what Mazdatrix is selling. If you have a local drive shaft company in your town, give them a call. Maybe they have a repair. At a minimum they could inspect it and check it for straightness and balance.

My racecar's drive shaft doesn't start to vibrate until 7200 in 4th. It stops at about 7700. RX7's are a pain in the *** as far as driveshafts are concerned. The problem is that the engine is not mounted straight in the car from the factory - it is angled to the left. Mazdaspeed sells a two piece shaft to correct this on racecars.