DSMRevolution
20+ Year Contributor
- 1,630
- 10
- Dec 6, 2002
-
Sioux Falls,
South_Dakota
Well, the is my opinion anyways.
I rebuilt my transmission about 8,000 miles ago and ever since I have been using Pennzoil Synchromesh. It is the same product that you can find at GM dealerships (part #12345349). The Synchromesh is safe to use in our transmissions (in other words, safe to use with our brass blocker rings) but it never felt quite right in my transmission. Don't get me wrong, it is a fantastic product but for me it felt like I was shifting the transmission without fluid in it at all (rough gear engagement, etc).
Within the 8,000 miles I have changed the Synchromesh fluid 4 times (a little excessive but wanted to make sure it was clean after the rebuild). Each time I drained it and it came out almost identical as it went in (a little dirty but this is a given). Anyways, I wanted to do a experiment. I decided not to change my transmission fluid for about 4,000 miles of city driving.
Yesterday I changed the fluid and it looked quite different then when it went in. It was somewhat milky and it glittered on the way to the drain pan. Not something that made me . Looking at my options I decided to change fluids to see if I would notice any difference in shifting or fluid draining (milky ness, metal particles or flakes etc). I purchased 3 quarts of Coastal (which is safe for our transmissions also) 75w-90 ($3 quart) and after pouring that in I went for a test drive.
Much better. Transmission shifted through all gears smoother then it ever has. Previously using the Synchromesh caused hard engagement into first and reverse gear. When any other gear would engage I would feel a small clunk in the driveline if I didn't rev match perfectly. Using the Coastal fluid made a huge difference in my manual transmission over the Pennzoil Synchromesh. The small clunk I felt is totally eliminated and all other gears engage smooth including first and reverse (reverse is still a little notchy but that is because it isn't synchromeshed).
*Incase your wondering, I believe that the small clunk I felt was one of the sliders engaging the hub over the blocker ring and gear.
Anyways I just thought I would share my experience. I am not by any means saying that the Synchromesh is a bad product, it just didn't work for me. I figured some of this information might be useful for somebody!
More Information:
Coastal Gear Oil "trials"
Pennzoil Synchromesh Information
I rebuilt my transmission about 8,000 miles ago and ever since I have been using Pennzoil Synchromesh. It is the same product that you can find at GM dealerships (part #12345349). The Synchromesh is safe to use in our transmissions (in other words, safe to use with our brass blocker rings) but it never felt quite right in my transmission. Don't get me wrong, it is a fantastic product but for me it felt like I was shifting the transmission without fluid in it at all (rough gear engagement, etc).
Within the 8,000 miles I have changed the Synchromesh fluid 4 times (a little excessive but wanted to make sure it was clean after the rebuild). Each time I drained it and it came out almost identical as it went in (a little dirty but this is a given). Anyways, I wanted to do a experiment. I decided not to change my transmission fluid for about 4,000 miles of city driving.
Yesterday I changed the fluid and it looked quite different then when it went in. It was somewhat milky and it glittered on the way to the drain pan. Not something that made me . Looking at my options I decided to change fluids to see if I would notice any difference in shifting or fluid draining (milky ness, metal particles or flakes etc). I purchased 3 quarts of Coastal (which is safe for our transmissions also) 75w-90 ($3 quart) and after pouring that in I went for a test drive.
Much better. Transmission shifted through all gears smoother then it ever has. Previously using the Synchromesh caused hard engagement into first and reverse gear. When any other gear would engage I would feel a small clunk in the driveline if I didn't rev match perfectly. Using the Coastal fluid made a huge difference in my manual transmission over the Pennzoil Synchromesh. The small clunk I felt is totally eliminated and all other gears engage smooth including first and reverse (reverse is still a little notchy but that is because it isn't synchromeshed).
*Incase your wondering, I believe that the small clunk I felt was one of the sliders engaging the hub over the blocker ring and gear.
Anyways I just thought I would share my experience. I am not by any means saying that the Synchromesh is a bad product, it just didn't work for me. I figured some of this information might be useful for somebody!
More Information:
Coastal Gear Oil "trials"
Pennzoil Synchromesh Information