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NV4500? 5 speed 3rd gear synchro going out? 1994 K3500

jrsavoie

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NV4500? 5 speed 3rd gear synchro going out? 1994 K3500

It seems the 3rd gear synchro is going out in the 1994 K3500. That is a NV4500, correct?

I've never torn into a transmission or differential before.

The trans is grinding going into 3rd gear. If you don't rev up to normal speeds in 2nd and shift excrutiatingly slowly the grinding can be avoided.

Can anybody give me advice or parts numbers for what will be needed?

How big a job is this? Is this best left to a guy that knows trannys well?
 
Check 5th gear nut on back of tranny,its known to loosen up and give shifting problems from tranny whining to grinding gears and loss of 5th all together
 
I thought the 5th gear nut is only a dodge problem but I might be wrong.

My 94's synchro went out and now there in no way to stop from grinding (3rd is always the 1st to go, then 2nd, then 4th, 2nd will eventually lock up as well as 3rd, dont ask how i know, lol) the poor truck has been very abused and neglected.

My 93 is at the take it slow stage now and it does help to rev to proper speed before shifting up or down into it. Looks like I will be lining the NV4500's up for some R&R.
 
I agree with tanman, to my knowledge, the GM transmissions had a different mainshaft and fifth gear than the NV4500HD (only found in v-10 and cummins applications) so afaik, they are immune to the problem. the GM version is the NV4500LD, which has a lower GCWR than the HD version (19K vs 21K, afaik)

I concur with Devin on quad4x4.com. while I havent ordered from them, they at least appear to have thier crap together, and are quite fair on pricing. I havent come across any inaccurate info on their site either.

make sure to run the castrol syntorq lt, or get some amsoil equivalent from wrecker.
 
If anybody sees a good NV4500 worth buying for sale, give me a heads up.

The local mechanic gave me an estimate of $700. Which for pulling and replacement doesn't sound to bad, but it is still more than I have to spend right now. Especially if the trans needs more parts than the guestimate. No way of knowing til it's out of the truck.

If anybody is willing to help me with it I could pull it out of the truck and tote it to wherever. I'm a little nervous about diving into something new these days. I rebuilt gear reducers & transfer cases but never a transmission.
 
no sir, as I am sure the international has the SAE bellhousing pattern, which is far larger than the GM pattern. I hear that a good quality set of snap ring pliers is all you need for specialty tools, all the rest can be done with common tools. I do honestly think a call to quad 4x4 would ease your worries. they have tools, manuals, and ALL the parts one would ever need for the 4500. 4wd will really limit cost effective swaps, so I am afraid you have to go with rebuilding it, or swapping for an identical one.

a quick check to car-part.com reveals that you guys get your wallets assaulted, those are some high prices! I did find one on e-bay though:
http://cgi.ebay.com/ebaymotors/Chev...ptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories

keep an eye out. a week or two ago, there were some good used takeouts selling for 500-850. that would give you something to run for a while hopefully, and take the time to rebuild yours yourself.
 
[url said:
http://cgi.ebay.com/ebaymotors/Chevy-GMC-NV4500-5-speed-Manual-Transmission-_W0QQcmdZViewItemQQhashZitem27ba3e9c13QQitemZ170628389907QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories[/url]

keep an eye out. a week or two ago, there were some good used takeouts selling for 500-850. that would give you something to run for a while hopefully, and take the time to rebuild yours yourself.

I good used trans in that price range would suit me fine.

We have 4 vehicles and there is usually at least one in need of repair.
Right now the Interbational needs a right rear rotor,
The 96 Suburban has a vibration - have to get the driveshaft checked again as BSI's reputation has gone down hill. - That's the place I took the drive shaft to have it balanced. Now I still don't know that the drive shaft is not the problem. The guy I took problems like this since 1974 has up and gone away.
The 95 Tahoe and the 98 Suburban need to be serviced & the Tahoe needs something. Timing at least
The 94 K3500 needs a transmission
 
I good used trans in that price range would suit me fine.

We have 4 vehicles and there is usually at least one in need of repair.
Right now the Interbational needs a right rear rotor,
The 96 Suburban has a vibration - have to get the driveshaft checked again as BSI's reputation has gone down hill. - That's the place I took the drive shaft to have it balanced. Now I still don't know that the drive shaft is not the problem. The guy I took problems like this since 1974 has up and gone away.
The 95 Tahoe and the 98 Suburban need to be serviced & the Tahoe needs something. Timing at least
The 94 K3500 needs a transmission

I feel your pain, it is hard for me to have atleast 1 truck that isn't under the weather at all times... I hope I can change that now that I am graduating and should have time to turn a wrench.

95 6.5 needs a tranny rebuild, 2 tires, front brakes, new injectors again, and I have a vin F manifold swap to do.
94 6.5 needs new everything, except rear axle, frame, cab, and fenders. LOL.
93 6.5 needs a turbo, exhaust, and guages.
And I still think I need a project truck
 
my truck repair list exceeds my monthly income. :( good thing I was really good at putting 90 percent of my high school income towards savings... 99 needs a bypass filter, 95 needs an engine, 95 GMC needs a pickup box and a b&w, 94 sub needs an engine, 91 gmc needs a fluidampr, 91 chevy needs a front end, a clutch, and a rear end rebuild.
 
my truck repair list exceeds my monthly income. :( good thing I was really good at putting 90 percent of my high school income towards savings... 99 needs a bypass filter, 95 needs an engine, 95 GMC needs a pickup box and a b&w, 94 sub needs an engine, 91 gmc needs a fluidampr, 91 chevy needs a front end, a clutch, and a rear end rebuild.

Savings?! What is this word? lol I spent all mine getting through college and starting a farm. Now I have saved some and it is time to start repairing all my trucks.
 
I'm embarrassed to admit what I spent all my savings on.

Right shoulder, Left tricep, right foot, eyes, ticker, scotch, beer, married a before I could get a class C license, Kids, kids , kids, grandkids, Ski trips, hunting trips, fishing trips, shooting sports, boating - at least it wasn't all a waste. LOL
 
I agree with tanman, to my knowledge, the GM transmissions had a different mainshaft and fifth gear than the NV4500HD (only found in v-10 and cummins applications) so afaik, they are immune to the problem. the GM version is the NV4500LD, which has a lower GCWR than the HD version (19K vs 21K, afaik)

I concur with Devin on quad4x4.com. while I havent ordered from them, they at least appear to have thier crap together, and are quite fair on pricing. I havent come across any inaccurate info on their site either.

make sure to run the castrol syntorq lt, or get some amsoil equivalent from wrecker.
Sorry,fifth gear nut can and do come loose on GM NV4500.I seen it on 2 diff trucks last year.
 
well I did do some more research, and while they do have a different mainshaft and gear, they have a similar gear and shaft design to the HD version, so therefore they can, and as you saw, do spin 5th gear off. but the point remains, it doesnt seem to happen nearly as often to the LD version as it does the HD version.
 
OK, I am getting a tranny that the guy said is hard to shift into 3rd sometimes. How hard are the synchros to change if I already have the tranny out of the truck ?
I did one from a dodge a long time ago. All i remember was that it was a pain in the azz to get it apart and that the gear teeth are extremely brittle and chip very easy
 
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