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Discussion Starter #1
New owner of an 06 RCSB 4x4 Silverado that has the stock 4.3L v6 and 5speed manual tranny with 80,000mi on the clock. Motor and drivetrain are stock other than a catback dual exhaust.

Coming from a tuned LMM duramax this thing is definitely a slouch, but priorities have changed and I just need a truck to commute to work and back.

Seeing that I'm driving it, I might as well have some fun. When revving it out it's almost impossible to speed shift from 2nd to 3rd. From what I've read this is somewhat common on these transmissions.

Anyone try swapping to a short shifter like the one from Core Shifters, they claim over 20% reduction in throw with a firmer, smoother shift. http://www.core-shifters.com/servlet/the-526/Core--fdsh--Hurst-shifter/Detail



Is there any noticeable benefit while shifting, or strictly for "show" ?

Also, I have no idea if the fluid has ever been changed or not... What are most of you running? Are there any additives worth using to smoothen things out?

During normal driving it seems to shift well, other than a slight shudder when starting off in 1st if you're not on the gas. Also tends to whine when down shifting especially 1st gear. Clutch seems pretty firm and has to be right to the floor to release, any recommendations for it?

Any insight is appreciated!
 

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I have a short throw shifter from that same ebay seller on my NV4500. Its a night and day difference in feel and performance! Its like shifting a sports car.

The whine you talk about sounds normal but it wouldn't hurt to change the fluid.

The high rpm shift problem is typical for it seems most 2000s era GM manuals. I know on camaros they had an orifice in the master cylinder restricting flow causing slower shifts. I don't know about trucks specifically though.
 

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Discussion Starter #3
I have a short throw shifter from that same ebay seller on my NV4500. Its a night and day difference in feel and performance! Its like shifting a sports car.

The whine you talk about sounds normal but it wouldn't hurt to change the fluid.

The high rpm shift problem is typical for it seems most 2000s era GM manuals. I know on camaros they had an orifice in the master cylinder restricting flow causing slower shifts.
Thanks for the reply! Good to know someone has had good experience with it, pretty sure the NV4500 is practically a bigger NV3500 so the results should be the same. Did you have any issues with your 2/3 shift before? Notice an improvement?

I read something about some sort of drill mod to the master cylinder to help release the clutch faster... but I'm not 100% certain.
 

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Bitchin' Stitchin'
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I have one of the 'Core/Hurst' shifters. NV3500.
Positively absolutely one of my top 3 mods!
Shift gates are very similar to the feel of the Hurst Comp+ I had in my L-78 Nova.
I've had gear-head buddies riding shot gun comment on how short the throws looked as I go through the gears.
Had to rebend the arm somewhat. 3rd & 5th were pretty close to the dash (GMT400) but we did the heating under where the top of the shifter boot is.
And the fitment of the supplied boot wasn't all that great. So I stitched one up.

shifterbootII082_zps9365e4e8.jpg


Highly recommended!
 

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"The Man"
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Funny, i went from a 2007 LMM duramx to a 2006 4x4 RCSB silverado with the 4.3 and a 5 speed as well. It too had just under 80k miles. lol. I ended up swapping the 4.3 out with a 5.3 and dont plan to look back! I was unaware they made a short throw shifter for this transmission. Looks like ill be in the market for one too.
 

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Discussion Starter #7
Funny, i went from a 2007 LMM duramx to a 2006 4x4 RCSB silverado with the 4.3 and a 5 speed as well. It too had just under 80k miles. lol. I ended up swapping the 4.3 out with a 5.3 and dont plan to look back! I was unaware they made a short throw shifter for this transmission. Looks like ill be in the market for one too.
That's funny you're in the same boat as me! If I plan on keeping the truck for a while I will also be looking into an engine swap. I was thinking about going straight to a 6.0L but I don't know how long that NV3500 would last. Why did you go to a 5.3, any serious complications doing the swap?

For now the ol' 6 banger will have to do, I don't plan on dumping that kinda money into it right now.

So far I've heard nothing but positive feedback about the shifter, with no complaints whatsoever. I think it's something I'm really gonna be looking at getting in the near future. Have to figure out if it's possible to swap the manual tcase knob as well, can't have mis-matched knobs HaHa!

Also tried double clutching on my 2-3 shifts today and it seemed to help.. Maybe the clutch isn't disengaging fully...
 

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Thanks for the reply! Good to know someone has had good experience with it, pretty sure the NV4500 is practically a bigger NV3500 so the results should be the same. Did you have any issues with your 2/3 shift before? Notice an improvement?

I read something about some sort of drill mod to the master cylinder to help release the clutch faster... but I'm not 100% certain.
I never ran the factory shifter, I went straight to the Core Shifters short throw. This was a swap done on my '84 K10 from the original SM465. But otherwise I have no problems with the 2-3 shift.

The drill mod is what I was referring to. I don't know if that applies to nbs truck master cylinders though.
 

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"The Man"
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229 Posts
That's funny you're in the same boat as me! If I plan on keeping the truck for a while I will also be looking into an engine swap. I was thinking about going straight to a 6.0L but I don't know how long that NV3500 would last. Why did you go to a 5.3, any serious complications doing the swap?

For now the ol' 6 banger will have to do, I don't plan on dumping that kinda money into it right now.

So far I've heard nothing but positive feedback about the shifter, with no complaints whatsoever. I think it's something I'm really gonna be looking at getting in the near future. Have to figure out if it's possible to swap the manual tcase knob as well, can't have mis-matched knobs HaHa!

Also tried double clutching on my 2-3 shifts today and it seemed to help.. Maybe the clutch isn't disengaging fully...
If i were to do it again i would just go with the 6.0, i initially was going to do the 6.0 but since i daily the truck i figured id come out ahead as far as gas millage by going with the 5.3, and it would still be a significant power gain over the 4.3. Now that ive done it, added long tubes, o/r y pipe, single chamber exhuast, intake and a tune... millage isnt really all that wonderful anyway lol. I may swap it out down the road. The NV3500 is holding up fine with my current setup, and i dont see it giving me any issues with the new power level. As for the swap, fairly easy. Can be done within a matter or 3-4 days if you have all the parts already there. Someone to help you makes it a lot easier, i did mine by myself other then a buddy helping me pull the 4.3 out.
 
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