Madmarek

Recently purchased an 84'. This is my first manual shift car. It seems like when its cold it shifts better,(I can find 2nd easily and 3rd does not grind)
4th and 5th feel like they should.

Anything I can look at to see if I can improve 2nd and 3rd. Change the oil, replace bushings etc?

I want to know if there are any simple things to look at before I bring it to a shop. This car is a mystery to me. I am used to American musclecars etc.
Any good books on mantenance. I have the service manuals on CD. Tough to navigate through.

85fortheDrive

Some questions, which I hope will lead to answers...

What are the symptoms in 2nd and 3rd that are causing you concern? How does reverse do? Any grinding? What's the play like in the clutch? Do you have the standard long arm throw shifter or did the previous owner put in a short throw shifter?

Replacing the tranny fluid isn't too bad and might be a decent place to start.

Madmarek

Just keep in mind this is my first Manual car.

Finding 2 from any gear can be difficult. Sometimes I push it forward then have to push harder and it will pop in. Sometimes it just slips in like 4th and 5th do.

3 slightly grinds unless I match the RPM's perfectly.

Reverse is fine no problems at all.

Not sure about play in the clutch. Seems to start to engage at 1/3 from the floor. No roll back on a hill from this point onward. Never had a clutch before so I don't know any better.

I don't think it has a short shifter since the little springs and clips are there under the leather boot.
As for fluid change, how and where do I check? What type and how much.

SMTCapeCod

Nice looking car, love that color.
You'll need to spend a little time checking through the archives here. Some folks have had luck with improving shift quality by switching to Redline synthetic fluid. You (or a 928-familiar mechanic/enthusiast) should also check to be sure that the clutch circuit is working right and that you aren't losing fluid or getting air into the system. The older trannies are just clunky and the shift linkage is vague...but steps can be taken. There is also an old trick of running a hose clamp around the front of the linkage to just snug it a bit..
Bring it up to the Boston Shark Party on Sat at Larz Anderson, some knowledgeable folks can give you the skinny on some of these points

hacker-pschorr

No
Double no

I may be one of the lucky few, but my 81 is very smooth into every gear and is far from clunky. The centering of my shift lever is perfect, settles right between 2nd and 3rd every time. Finding gears is second nature in my 81.

The problem is over the last 20 years most double disc 928's were in the hands of mechanics that had no clue what they were doing. Driving around a 928 with an improperly adjusted double disc clutch will cause you to own a clunky, grinding clutch (eventually worn 2nd gear synchros like our friend here probably has).
Not to mention the shift linkage is one item that almost receives no attention unless something completly breaks.

I drove two other duel disc 928's this past weekend. If they are the "norm" of what most OB owners experience I can see where this opinion is coming from. One had a short shift lever installed so that probably explains it. Ther other had a cut down shift lever, so I was thinking that expalined that one.....not sure.

I've been lucky that my 928 has been under the care of a very dedicated 928 enthusiast since 1991.

laneskelton

When these trannies are in good working order they should shift very positive, and fairly smooth without any grinding at all. My tranny shifts perfectly, but it was rebuilt about 40,000 miles ago

JKelly

First check the rear coupler bushings. The rear coupler is above the torque tube and back near the transmission. You'll probably have to wrangle the rubber boot rear-ward in order to see the coupler and bushings. If they are crumbled or if you are missing one (or two), it will affect the ability to shift from 1st into 2nd gear.

Definitely change the gear oil too.

classic_cars

Does the short shifter kit contribute to a poor shift?

Madmarek

Thanks I will try to look at the bushings this weekend. How do I check/replace the tranny fluid.
I don't see a dipstick. Is the tranny and differential fluid in the same compartment. I don't want to overfill since this is a big no no on automatics. Do I just use regular gear oil? How much will it take.

hacker-pschorr

Depends on who you talk to. Most cars with a short shifter have a much more "direct" shifting feel some call notchy. I personally like the feel of a short shifter, many do not. Even with a short shifter with everything else working, finding the proper gear should not be difficult in a 928.

kjurkic

MADMAREK:
If your car is shifting good when cold, but getting fussy when warm, then you might want to move to a higher "weight" lubricant. Most likely to P.O. used the standard 80-90 weight gear oil. With transmission lubricants, there is so many choices out there, and changing transmission fluids is so cheap, that it is worth a little experimentation.

My 80 5spd was OK, when cold, getting bad when warm, so I tried a blend of Dexron III ATF, synthetic high-pressure oil, and 80-90; this blend has worked fantastically well in my Supra for the last 5 years, but did not make any noticeable change in my 928. Now I run 90-140 weight, and my problem is that shifting is a bear when cold, but quite nice when warm. Unfortunately, my 2nd gear synchro is so far gone that alchemic wizardry has reached its limit here. The other caveat is that the trans & differential share the same fluid, so if you have the limited-slip, playing with fluids will change its behaviour, and possibly do damage in the long run.

Since it seems no-one else has answered your question on how to check fluid- There isn't any dipstick on manual transmission cars.

You will need to get the car up in the air on a lift or jack stands. There is a fill-plug on the back side of the differential that you can remove, and stick you finger in to see if the oil is at that level.

On my 80, I use the the drain plug that is at the front of the transmission (probably the wrong one) for emptying. Both of these require a 17mm allen head tool. I fabbed mine out of a bolt with a 17mm head, and a couple of nuts jammed together on the shaft.

HTH
Ken

Vilhuer

To get all oil out both front and back drains need to be opened. If just one is opened its better to open front as less old oil is left in.

Madmarek

Thanks for the reply on the how to check.
Whats the standard amount and viscosity?
Do I need to use different fluid if its a limited slip?
I will most likely go with synthetic like amsoil etc. unless someone chimes in.
I have a lift so getting at stuff is not a problem.

JKelly

Also, here's my Gear Oil Filler for you to use :

https://rennlist.com/forums/showthre...gear+oil+stick

Fogey1

REMOVE THE FILL PLUG BEFORE YOU REMOVE THE DRAIN PLUG!!!

No matter how bad your shifting is, an empty trans that you can't refill is worse.