While searching the web yesterday on the topic of synchromesh fluid I cam across a Honda forum thread, evidentially some of the Honda people are using GM fluid in their cars to ease shifting and prolong transmission life. What I found very interesting was that some of them say that the GM fluid is not the same as the Pennzoil fluid and they claim it is better. It is claimed that the GM fluid is a modified synthetic not a full synthetic and that gives it properties better suited to the manual gearbox. I had put the Pennzoil in mine and it leaked out the axle seals like crazy. I put 5W-30 back in along with some AutoRx seal conditioner and the leak has stopped. I am going to put in the GM fluid and see if it will stay in without leaking. The shifting action is very smooth but I have a slight grind into 5th and I am hoping the GM fluid will alleviate that.
It didn't solve my issues (occasional difficulty into first, grab into third). However, 2nd, 4th, and 5th are remarkably smooth. Even 1st and 3rd feel better, though not 100%.
I haven't had problems with leaking, but my seals are not your seals. Your experience might vary.
It may have changed over the years, but long ago from my own experiences, I ran away from anything Pennzoil or Quaker State. I still wont use anything from either of them. Once I turn away from something, it takes a lot to get me back if ever. Both of them seemed to manufacturer tar/sludge inside of an engine.
Yes, I have heard the same thing Roger and I had a friend with a VW Passat just a couple of years ago that lost an engine from having the oil changed every 3k with Pennzoil. There was so much sludge in the motor that the oil light came on for low oil pressure. I just got home from buying the GM synchromesh fluid and it says right on the bottles that it is semi-synthetic so it isn't the same thing as the Pennzoil product which from what everyone has said is fully synthetic. The label also says it contains benzene.
seldom will fluid cure a grinding noise!! 90 % of Fiero shifting problems are related to the clutch slave cylinder all Fieros need the installation of the dual seal piston use Rodneys dual seal slave cylinder or install the 2 seal piston in your clutch slave the dual seal piston cures 10 other Fiero shifting problems by giving a stiff deep satisfying plunge make sure you have well over an inch of satisfying rod movement
THE #1 FIERO PROBLEM IS THE CLUTCH SLAVE CYLINDERS 1 SEAL PISTON REPLACE THE CLUTCH SLAVE PISTON WITH RODNEY 2 SEAL PISTON,, RODNEY IS A FIERO Magician & his 2 seal piston is magic bringing Fiero,s back from the dead
[This message has been edited by uhlanstan (edited 05-10-2014).]
I agree with Roger regarding the sludge buildup. Pennsylvania crude is reported to have a high paraffin content. Under high engine heat conditions and engine blow-by contamination, it coagulates on the engine block surfaces, including the inside of oil passages. This isn't a problem with the manual transmission, as there is a much lower operating temperature and there is no outside contamination.
Changed out the tranny fluid to the GM synchromesh today and took the car for a drive. The shifting was excellent and no leaking from the axle seals but I still get a slight grind when shifting into 5th gear. I had my wife depress the clutch pedal and I measured slightly over an inch of slave travel, I had her release the clutch and depress it again and the travel was less than an inch. I have an after market slave on the car and I put Rodney's double piston in it but I guess it is still not working well, so my next step is to install Rodney's slave cylinder. I guess as I go thru gears the slave travel decreases so when I get to 5th gear it isn't moving quite enough and causes a slight grind.
Changed out the tranny fluid to the GM synchromesh today and took the car for a drive. The shifting was excellent and no leaking from the axle seals but I still get a slight grind when shifting into 5th gear. I had my wife depress the clutch pedal and I measured slightly over an inch of slave travel, I had her release the clutch and depress it again and the travel was less than an inch. I have an after market slave on the car and I put Rodney's double piston in it but I guess it is still not working well, so my next step is to install Rodney's slave cylinder. I guess as I go thru gears the slave travel decreases so when I get to 5th gear it isn't moving quite enough and causes a slight grind.
Slave movement has no relation to what gear you are in. The slave pushes the clutch fork that in turn pushes the release bearing and that disengages the pressure plate. You can be in 1st, 5th or reverse and the clutch system works exactly the same.
Compared to the Pennzoil I would say it is even smoother. I do realize that the gear you are shifting into has nothing to do with slave travel, what I was saying was that the slave is losing some travel after shifting thru the first few gears and by the time I shift into 5th there's not enough movement to completely dis-engage the clutch, hence the slight grind. I have read elsewhere that the clutch is very sensitive to the correct amount of slave travel and even if its a eight of an inch to little it can cause a grind.
