rx7learner

I posted earlier about cliks and vibration in my driveline and was guilty of not reading prior posts well enough. I did the research (read for a couple hours) and put the car in 1st and rocked it to see if I heard the same noise and nothing. Went to the next cheapest possible solution and drained the rear dif, but I glanced up at where the drive shaft mates up with the tranny and saw the car was soaked with gear lube that leaked from where the tranny mates up with the driveshaft.

I installed the engine and tranny myself about 6 months ago... I knew I was smelling that nasty stuff the last couple weeks plus my shifting got progressively difficult (should have picked up on the hints)...

None the less... here are my questions...

Other than the tranny mounts not being set up and tightened correctly, could there be another cause for the leak where the shaft mates with the tranny?

I also know that my tranny is low on lube now... I read a post about mixing in some auto ATF with 75 90 gear lube. Is this safe / recommended?

Any help appreciated. 85 gsl Thanks

Rogue_Wulff

The rear seal on the trans is prolly leaking. This can be due to a bad seal, or the front u-joint could be bad, and this has worn the tailshaft housing bushing allowing the front of the shaft to have excessive play.
Check to see if you have excessive play where the shaft exits the trans. If so, you need to replace the bushing and seal. If no excess play is evident, a new seal may be all that is needed.

rx7learner

Thanks Rogue... I checked for exessive play and appear to not have any which would lean towards me just changing the seal, however I'm a bit skepticle that my tests were good enough because even though the leak is obvious I did have clicking upon hard acceleration and on turns as well as vibration > 60mph coasting or in gear (unless that could be caused by low tranny lube???). I read these could be caused any of the following... ujoints, breaks, rear diff lube, bearings and wheel balancing (but I ruled out wheel balancing because I not only had vibration but clicking also).

Ths steps I took to check the ujoinst are as Kent mentioned in another thread... put the car in first gear and rock the car back and fourth with the break off and listen for noise. I heard none. I also turned the shaft by hand and both the rear and front ujoints turned immediately, however switching back and fourth there was less than 1 quarter inch free play before turning the other direction.

I also drained my rear diff which had fresh syn lube I put in it about 9 months ago so I it was not lack of lube or bad rear diff lube because it still looks fresh.

When I manually spin the rear wheels they make no odd noise and they have no play twisting them so I dont think it is bearing related.

My breaks are fairly new and the calipers are in good working condition.

Other than the rear seal I dont see anything evidently needing repair. I know I probably am misdiagnosing this, and if in reading anyone has some additional test or corrections to the tests I have done PLEASE PLEASE let me know. I'm at a loss. Thanks.

Rogue_Wulff

Drop the driveshaft, and move the ends around. Any stiffness or binding will indicate the u-joint is bad. This can be the cause of the clicking/popping you have been hearing. A binding front u-joint can easily cause the rear trans seal to leak, and if left alone long enough, can also wear out the bushing inside the tailshaft, or even ruin the tailshaft housing.
Unfortunately, the u-joints in an 85 are "non-serviceable". You can take the driveshaft into a shop that specialises in driveshafts, and have it rebuilt for around $100-150, or they can make you a new one ($200 or more).

GavinJuice

You should have NO freeplay in those u-joints. Zinch-Zero-NADA. Follow Rogue_Wulffs advice.

rx7learner

You are correct. Just to clarify the freeplay was not in the ujoints themselves rather in the rear diff.

I followed Rogue_Wullfs advice and pulled the driveshaft. I removed the 4 bolts connecting the shaft to the rear diff and slid the other side out of the tranny.

2 things...

1 no fluid came out of the tranny (I sure hope I didnt cause any damage driving it with low fluid... it still shifted and did not sound bad so I'll keep my fingers crossed

2 that rear joint which appeared to have turned so well with no play is SHOT... once off the vehicle I could really twist and turn it.... only then it became obvious that it was very bad.

Thanks Rogue...

Attached are some pics for future reference...

Now its time to find a place that will fix it in Tampa???? Any suggestions appreciated... Otherwise I will post back with more pics and info after the rebuild.

Rogue_Wulff

No fluid coming out is not a problem. The normal "Full" level will not be high enough to leak out the rear, unless the front is raised higher than the rear. Just be sure to drain/refill the trans after installing the new/rebuilt shaft.
The rear joint does look pretty bad. You may find that one or both of the yoke halves are are bad.
I have no clue who to send it to, just get out your local phone book, and look up shops listed under "Drivetrain". Get quotes, and compare to the cost of a new shaft from Mazdatrix. They offer 2 versions. OEM exact replacement, and Mazdatrix custom. The latter comes with replaceable joints.

rx7learner

All the driveline places around here all want to charge as much as mazdatrix aftermarket. Even with shipping costs. I am just going to order it from them. Thanks.

rx7learner

OK... this shop is very professional and reasonable... I brought my driveshaft in to have the old non replaceable ujoints replaced with the replaceable ujoints intended from rockforddriveline.com (part number 430 10A) and he removed the old ones and installed the new for 22$ labor on each end (which was a bargain because I tried and its DEFINATELY worth 22$ plus not risking the damage to the yolks and shaft) and the actual ujoints were 36$ a piece.

To look out for anyone who is in the same boat, but that doesnt have a shop around them I asked whether they would accept a shaft that was shipped to them... and they said yes.

The shop is called PYRAMID
the address
3231 46th Ave N
St Petersburg FL 33714

Contact machinist is Ray Eanes... and the number is (727)527-5764

The shaft is back in and no vibrations and SMOOOOOTH... I'll post some pics later so that everyone can see the quality of the work.

rx7learner

The pics I mentioned

Rogue_Wulff

I dropped off my original '83 driveshaft at local shop today. The u-joints they are going to install have the grease zerk in the cross, not the cap. They had another shaft sitting on the counter, waiting for the owner to arrive. It was for a different model mazda, but uses the same u-joints.
Hopefully, I will have the same results. I'm tired of getting shook all over the place. I bought a used shaft for $10, felt good, but still has a shake to it. The old one didn't shake, but sure made loud noises. Front joint was toast.

rx7learner

I was really surprised at the difference. I get over 100mph without any vibration where as before 80 felt like I was going to throw the sunroof off.

I was expecting a slight difference but wow... the wierd thing is that it almost seems like I lost power with much smoother acceleration. Go figure....

But so far I consider it the best money for the improvement (runner up being the 2nd gen coil pack).

Whats odd is where you said the grease fitting was. Considering that I heard rockford was the only maker of the ujoints for our cars and I know thats where mine came from... why would yours be different? (mine is 85 N/A 5spd part number 430 10A)

In researching I also saw a post that someone snapped off the zirc fitting on there new ujoints because it protruded to far. I can safely say that where mine are at is not causing any problems.

Just mentioning it in case you want to follow up.

Rogue_Wulff

I know the feeling. My butt got numb on the ~700 mile round trip the day after I installed the replacement shaft. I woulda been more upset about the driveshaft having a vibration, but I bought it and a trans for $30, and the trans is good. I remeber how smooth the original was, even after it developed the popping/clicking. I just didn't have the time/money to get it rebuilt before the upcoming event. That was late Oct. By the time Nov was over, the car was destined to sit most of the winter, due to all the snow/ice. Now that it finally thawed out, I dropped the shaft off to be rebuilt. I'll put it in this weekend. Only 2 weeks till the 1st AutoX, so time to check the whole car over with a fine tooth comb, as the saying goes......

rx7learner

Guess what... It's an old post I know but the rear ujoint failed. Gonna bring it back to the shop and see what he wants to do about it... Seems like 1 of the caps just came right off. Had to drive 15mph for 10 miles on the veterans expressway in FL where normal is 75 to 80. 2 months is a short time before a failure and I really dont beat on my car. I just drive it to work and back 13 miles each way. We'll see how much this shop stands behind their work.

rx7learner

OK they put a new ujoint in and charged me another 50$. He said if it were poor workmanship or a defective part the problem would have happened earlier (not sure I agree with that), however if it lasts only a couple months again I'm buying a new shaft from MAZDATRIX... prolly should have done that to begin with.