Vtec CRX trans question

[AaronR]

OK,. here's one for the experts. I have a 89 crx si with a 95 Civic SOHC Vtec motor in it. The car is all modded up and runs really strong. Dyno'd at 127hp.

The problem: When the car is cold, or for the first 15 minutes or so the trans is great and works with no problems, noises, or anything.
Once the car is warmed up I get a 1st to 2nd gear crunch above 5000 rpm, and a 2nd to 3rd crunch at all rpm. My local honda dealer suggested redline 10w30 so I put that in, and it made the problem worse. The part I don't understand is that when cold or warming up, there are no issues, at any rpm, or anything.

Am I running the wrong weight oil in the trans, or do I actually need to have internal parts replaced?

Any help is much appriciated.....Thanks!
Aaron

 

[true]

Hey Aaron, it's internal. The early Honda cable transmissions (CRX/civic especically) are notorious for crunching 3rd gear. I've gone through a couple...it's generally cheaper to just get a new trans then to get new or sharpen your synchromeshes. A simple answer as to why its fine when its cold......the oil is thicker and the gears don't spin as freely. After the trans oil starts heating up it starts crunching as everything has less friction from the change in oil viscosity. Remeber, 10 when cold, 30 when warm (10w30). Unfortunately, that redline oil won't fix a thing...... I always use Honda 5w30 manual transmission fluid..but have also used any average joe 5w30..both work fine.

 

[AaronR]

True, thanks for the insight. Am I going to damage anything other than the trans if I keep driving it? I figure if I'm replacing the whole trans, I'll drive it until it gets worse...bad idea??
Aaron

 

[true]

Nah it should be fine...I know people who have driven with a grinding 3rd and 5th for a couple years (me ) The trans is really a closed system...bits of metal can't slip past the mainshaft and attack your clutch etc.. There is a magnet in the trans too that attracts those bits if metal from grinding gears. I would just say drive it till you can't bear it aynmore. If anything, try putting some thicker oil in there. Maybe give straight 10w oil a shot if you can find any (pretty sure they make it)....That obviously won't fix the ground down synchros, but may keep it from grinding as bad.