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**DONOTDELETE**
03-22-2001, 03:32 PM
I have 91' S13 155000miles, recently i feel my engine shakes between 70-75mph only at 5th gear near 3000rpm. Does it mean it needs to rebuild? Any additive helps?
thx

**DONOTDELETE**
03-22-2001, 03:34 PM
you sure it's your engine?

If it WAS your engine, I would guess that it would shake at the same RPM regardless of gear.

Maybe one of your tires need a balancing, or maybe it's worn out suspension bushings, etc.

**DONOTDELETE**
03-22-2001, 03:42 PM
check your T/C rod bushings.

Mav1178
03-22-2001, 03:47 PM
<BLOCKQUOTE><font size="1" face="Verdana, Arial[/img]quote:</font><HR>Originally posted by newbie:
I have 91' S13 155000miles, recently i feel my engine shakes between 70-75mph only at 5th gear near 3000rpm. Does it mean it needs to rebuild? Any additive helps?
thx<HR></BLOCKQUOTE>

If it is your engine at a specific RPM in a specific gear, I would check to see if your clutch is working okay. My original clutch slipped badly at 3000RPM, and it felt like a jerking motion.

If it is from your steering wheels, then it's your suspension and/or tires...

-alex

**DONOTDELETE**
03-22-2001, 06:46 PM
Could it be his engine mounts. It does have 155,000 miles. I just replaced mine and it made a huge difference in engine vibration!

Mav1178
03-22-2001, 08:02 PM
<BLOCKQUOTE><font size="1" face="Verdana, Arial[/img]quote:</font><HR>Originally posted by 93convert:
Could it be his engine mounts. It does have 155,000 miles. I just replaced mine and it made a huge difference in engine vibration!<HR></BLOCKQUOTE>

I doubt it... if it were bad mounts, the engine would shake at all RPM's...

-alex

**DONOTDELETE**
03-22-2001, 10:20 PM
I've got a 90 240sx 5spd. It's got about 94k miles on it. I just recently rebuilt the engine. I've got about 400 miles on the rebuilt engine. I also bought an ACT clutch. I also experienced shaking around 3000rpms in all gears. It is most significant in 5th though, especially under deceleration. I would like to know what this could be also.
Thanks!
Rusty

mzf
03-23-2001, 10:46 AM
<BLOCKQUOTE><font size="1" face="Verdana, Arial[/img]quote:</font><HR>Originally posted by Mav1178:
I doubt it... if it were bad mounts, the engine would shake at all RPM's...

-alex<HR></BLOCKQUOTE>

But if one of the mounts was just a little bit damaged, wouldn't it maybe just resonate at certain rpms?

Mav1178
03-23-2001, 10:57 AM
<BLOCKQUOTE><font size="1" face="Verdana, Arial[/img]quote:</font><HR>Originally posted by mzf:
But if one of the mounts was just a little bit damaged, wouldn't it maybe just resonate at certain rpms?<HR></BLOCKQUOTE>

Hm... you have a good point. Don, Asad, etc, anyone want to add their theories on harmonics? http://www.freshalloy.com/

-alex

mzf
03-24-2001, 12:26 AM
<BLOCKQUOTE><font size="1" face="Verdana, Arial[/img]quote:</font><HR>Originally posted by Mav1178:
Hm... you have a good point. Don, Asad, etc, anyone want to add their theories on harmonics? http://www.freshalloy.com/

-alex<HR></BLOCKQUOTE>

Woohoo! I finally said something worthy. http://www.freshalloy.com/ I hate harmonics problems on my car. First it was the heat shield, then the baffles in the muffler, panels over the rear speakers, and god knows what else. Sheesh!

Actually my old car had a similar problem due to a tranny mount. It was brutal. The shifter would start shaking like crazy but only at about 2700rpms, mostly in 1st and 2nd. http://www.freshalloy.com/

**DONOTDELETE**
03-28-2001, 08:08 PM
Thankyou for all your replys, after I read all the replys and observed couple days. I figure out I have all to problems above, clutch is jerking bad sometimes, exhaust mid pipe hitting under car under my seat. I think I'm more aggree with mzf's idea that one or more of the mounts are wore out because I remember our KA24DE is totally unbalance engine that built for torque and low-end.

btw, is our 5spd stick directly to tranny or is cable driven?

JonCarson
03-28-2001, 08:39 PM
5spd manual is direct on all 240SX.

**DONOTDELETE**
03-28-2001, 08:41 PM
thankyou carsonjon