Hey people, I have and 87 NA with 170k on the odometer. Recently I decided to replace the trans fluid with Royal Purple gear oil, and since then, 3rd and 4th gear have been grinding. This happens mostly on downshifts over 60 mph, but it happens shifting up as well. My first assumption was that the transmission was going out and it would need to be rebuilt or replaced. However, I think my clutch is on its way out too. It works fine most of the time, but it slips when shifting quickly quite regularly.



Could a bad clutch cause my transmission to grind in this manner? Also, and this may be a separate issue, I have always had trouble with the trans grinding while shifting into reverse.



If the transmission is the culprit (as I fear it is) is it better/cheaper to find a transmission shop to rebuild it, or just buy a used transmission and install that?



And while I'm on the subject, are there any community favorites in the clutch department? I figure if I am going to replace one, I should probably do the other as well.



I appreciate the input!

Yes a clutch could definitely cause what you are describing. Every transmission I've had go bad I've just replaced, however that was only one instant in my GSL-SE. These tranny's are pretty rugged, but they do go bad. When you shift quickly you usually keep your RPM's high a clutch that's getting worn won't take to the high rpms.



I like the ACT clutches.

In my experience and this is mostly with Honda it's always cheaper to replace it then to have it rebuild unless by some miracle you know someone with the innerds that just wants to give them to you and you do the work yourself. So in that small non-existant percentage then it's cheaper. I actually have an S4 trans in my garage from an engine swap that I never used and should be in pretty good shape if interested. Not sure what shipping is but would let it go dirt cheap to see it out of my garage.

ACT clutches are pretty nice. I have an ACT lightened flywheel and clutch i my T2. Definately a nice upgrade.

If your clutch is old and worn out it may not be releasing from the springs and hangin up a bit causing the grinding...however if this just started when you changed the fluid it's always best to look at the last thing you did in that area. A great way to test your clutch is to do a clutch dump or a second gear start. But sounds like you know its bad. Do a clutch, if it's still bad you would want a new clutch on the next trans anyway.

Thanks for the replies guys. I did the second gear start, and it confirmed that the clutch is definitely in bad shape. So I will be looking at a new one, and hopefully that will cure the gear grinding woes. I will also see if I missed a step while changing the fluid and if there is something that's causing problems there.



However, if I do need a new transmission, I will definitely hit you up rtrypwr, and see if we can work something out.