edunnett

I was debating with my husband yesterday about driving techniques to preserve the manual transmission in our "new" '86 Civic with 130K on it. It has a bad third gear synchro so we're using the clutch a bit more in shifting nice and slow and I really want the clutch and tranny to last as long as possible. Questions are:

1) How bad is it really if he sometimes coasts (like down a hill or slowing for a turn) then puts it into a gear using the clutch? I contend that the engine and tranny will be very different RPM and that going from neutral to a gear while rolling is very hard on the car. We should either always try to keep it in an appropriate gear or learn to double clutch. What do others think? (btw - tranny already has bad 3rd gear synchro and shows evidence of prior repair with some adhesive holding it together and also previous owner had gear lube in there, i put syn motor oil).

2) We both sometimes take it out of gear to coast to a stop. Is there any harm done in not using the clutch when going from gear to neutral?

blackdelslo

You can rev match both the engine and tranny. I wasnt aware that you didnt need the the clutch to take it out of gear.

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<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by edunnett &raquo;</TD></TR><TR><TD CLASS="quote">

1) How bad is it really if he sometimes coasts (like down a hill or slowing for a turn) then puts it into a gear using the clutch? I contend that the engine and tranny will be very different RPM and that going from neutral to a gear while rolling is very hard on the car. We should either always try to keep it in an appropriate gear or learn to double clutch. What do others think? (btw - tranny already has bad 3rd gear synchro and shows evidence of prior repair with some adhesive holding it together and also previous owner had gear lube in there, i put syn motor oil).
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The purpose of the synchro is to 'ramp up' the speed of the shaft while shifting so that you don't have to manually match revs to prevent grinding. It's why we don't have to double clutch anymore. If your 3rd synchro is going, the best way to keep it alive would be to match revs before shifting. Also, it might be a good idea to leave it in gear, just to keep from shifting into gear twice (shift to third, neutral, then back into third) and putting more wear on the synchro.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by edunnett &raquo;</TD></TR><TR><TD CLASS="quote">
2) We both sometimes take it out of gear to coast to a stop. Is there any harm done in not using the clutch when going from gear to neutral? </TD></TR></TABLE>

Theoreticaly, not really. Even if you're upshifting, if you're good at matching revs, you can shift without the clutch. Popping it out of gear while slowing down won't hurt at all, because everything is rotating in sync, and you're just sliding the collar into neutral. Being in neutral does put more wear on the braking system though.

HyBriDcxR

There's nothing wrong with coasting. I'd rather waste my brakes then my tranny.

Brakes much cheaper to replace then a tranny.

Archidictus

Shifting techniques to preserve tranny:

Slowly and carefully.

dantastic

rev match and double clutch: for both up shifts and downshifts

JDMisGOOD

buy a new clutch and tranny...and be happy!screw fancy techniques

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<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by HyBriDcxR &raquo;</TD></TR><TR><TD CLASS="quote">There's nothing wrong with coasting. I'd rather waste my brakes then my tranny.

Brakes much cheaper to replace then a tranny.</TD></TR></TABLE>

But there's really no wear on the tranny that I can think of that would cause excess wear from leaving it in gear while stopping. The gears are constantly meshed and spinning; I guess in gear they spin faster in gear than at idle, but that's not going to make that much of a difference. Since the concern is with the synchros, by shifting out of gear to coast, then back in at speed, it will cause more wear on the synchro than just leaving it in gear.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dantastic &raquo;</TD></TR><TR><TD CLASS="quote">rev match and double clutch: for both up shifts and downshifts</TD></TR></TABLE>

The best way to prevent tranny wear.

Jokerluv

shift normal?

edunnett

Thanks for the comments back. My concern is that my husband likes to coast downhills and to slow down (engine RPM at 750/idle) then shift into a gear w/o rev matching (engine RPM and gear suddenly brought into synch at lets say 3000 rpm). I consider that "slamming" it into gear if there's no rev matching. I'd like some reason to convince him that's a really bad idea especially when we already know we're losing the 3rd gear synchro. Personally, I can double clutch/rev match and do so for downshifting. But what reason should I give him for not costing then shifting?
elissa

00Red_SiR

I would use the clutch to go from a gear to neutral...rolling up to a stop sign in neutral is better than gearing down because that is harder on the synchros. Wait till you stop before you select 1st gear to start off again. Rolling up to a stop sign in gear with the clutch pushed in isn't hard on the tranny.

hard shifting while going up throught the gears or gearing down to a stop is hard on the synchros.