Harmonic Engine/Trans. Noises?

[RHestand]

Any ideas as to why my truck makes these sounds at 1300 thru 1500 RPMs in 5th gear but not in 6th? This started after I had the new SBC-OFE clutch, flywheel kit inst. about 7-8000 mi. ago. It didn't do this with the stock setup.

SBC told me the truck would be louder without the DM flywheel, and I accept that, but why 5th and not 6th? I havn't pulled my 31 ft. camping trlr. with it yet, but I think it might be worse.

Before inst. the new clutch I inst. a new Fluid Dampner, so I can't plan on something like this making it better.

This is something I can live with, if it's not doing any harm, but I have to do a lot more shifting, so I don't have to hear it. It sounds like I'm lugging it really bad, but I don't think I am.

The new clutch works great, (it also has the clutch out/ neutral rattle) and Peter at SBC said it would get quieter with time.

So have any of you guys ran into this situation?

Thanks for any replies,

Ray

 

[JCleary]

It's normal. Torsional vibrations resonate at the 1-1 ratio in 5th gear. The springs on the OFE are stiffer than stock. You should have heard the racket on my '03 while pulling a heavy load in 5th with my dual disc! When I switched from the DD to OFE the trans was much more quiet, but still a bit louder than stock.



Really, you shouldn't be pulling in that rpm range anyway... Cruising along in an unloaded truck at that rpm is fine, but you should be turning higher rpm with a load behind you.

 

[JCasper]

My truck does the same thing although it is noisy in 4-6th at those RPM's along with the neutral rattle.

 

[MSchneider]

my sbdd does also.

 

[RHestand]

Thanks guys for the replies, and especially to JCleary for the 1-1 answer.

I new 5th gear was 1-1, but couldn't understand why it was louder there.

I have only been using my truck mostly for short trips (empty, 10-15 miles) back and forth to town at 40-45 MPH. That is the speed where 2 or 3 MPH either way brings out the rattle, and it gives my wife the opportunity to say, "What did you do to this truck?" I say " Nothing Dear. "

Oh well I still like the clutch, but I haven't tried my Smarty above #5 yet. Time will tell.

Thanks again, Ray

 

[JCleary]

Don't be afraid of level 9. The clutch will take it and then some... You may find it a bit smoky if you're running Revo software. My preference is the TNT. Much less smoke, at least on my truck. Seems to be better all around than the regular Revo program.

 

[MSchneider]

what is the diffrence between the revo and the tnt tune?