Hey guys i have an 87 NA RX7. Im replacing the bushings on my transmission (manual) and i have the car up in the air. Im reinstalling everything now but when i put my driveshaft back in, there a gap where it inserts into the tail of the transmission.... Is this normal?

I didn't take pictures of the before which i regret but here is that gap.


Any thoughts? This pic is taken with the shaft bolted to the rear diff.


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its not supposed to be butted up. its supposed to have a gap although that looks like a lot. not sure what the normal range on an FC is but it looks like theres a wear line on the shaft of where it "should" be. is the transmission or diff dropping down? put the car on the ground and check the gap again. it should close up some

is slayer your main?

 

I see that line that youre talking about. The entire car is on jack stands with the engine currently out. Transmission is on a transmission jack at the moment.

This is an aftermarket drive shaft and came with the car - is there any way to tell if this is an automatic driveshaft?

 

I just looked at mine and it is still the stock shaft. Mine has a spline? cover that keeps me from actually seeing what it looks like.
One the site are measurements for driveshafts auto vs. manual n/a. Also verify the rear dif is n/a and same with the transmition. I would be able to recognize the difference straight away between the two but I can explain it at the moment.

I would personally worry about it unless you are leaking fluid. However, this could be a rather large mistake. Hopefully, someone else willing to post can help.

 

is slayer your main?

typically auto driveshafts will have a different size yoke than the manual. not always the case. not familiar enough with the fc driveshaft to say. looking at some auto to manual write ups though, they do specify the auto driveshaft does not work. no one seems to say why, they just say it doesn't.

 

yeah the car is all stock. so the transmission and diff is all untouched from the factory. its an NA GXL. do you have a pic of what that cover looks like?


i see. so if this were an auto driveshaft it simply wouldnt bolt to a manual transmission or diff....i hope thats the case hahah

 

put the trans about where it would go if the motor were in and you'll get your answer. if it lands whereabout that line is then you're good

 

Gonna put this here for posterity.

I measured mine using measurement "L2" and its actually the correct one. Non turbo.

And some information about the automatic one. Note - this service manual is for an 87 RX7. These most likely differ for S5s.

 

Driveshaft lengths are the same for the S5.

 

That looks about right with a couple inches of the splined area uncovered. Like FDAuto said, look for the old marking.
*Actually it's hard to tell since it's aftermarket. Need to pull it and measure L1 if you're concerned.

Auto driveshaft would bolt to the diff, but it has a different spline pattern than the NA transmission.

 

My apologies to the first two posters, we all posted within minutes of one another. Had I saw those i would not have posted. I really don't need to make an even bigger *** out of myself so, I will duck out now. Best wishes to the OP and thanks for the help everyone.

 

Do you mean the lengths in the service manual picture i posted are the same for the S5? Or all the S5s are the same length drive shaft?

 

>> Do you mean the lengths in the service manual picture i posted are the same for the S5?

Yes. Driveshaft lengths in both S4 and S5 service manuals are all the same.

 

I am replacing my original driveshaft with a new one from Mazdatrix. It lacks the cooling collar that's pictured in the FSM picture.

I will probably have the same shaft exposure that caused your concern.

I'm assuming that the reason for the collar is to somewhat cool the rear seal on the transmission.

There is nothing I can think of to easily make a suitable replacement collar, so, I expect the seal to fail prematurely from the exhaust heat that it will be exposed to over time.

I will just have to check to see when the seal starts to leak oil.

Is it difficult to replace the oil seal? I will order a couple of spare seals ton be ready.

 

Might answer some questions here ...