Hey all. I just put a SBC 3850# 12CB DD and a newly rebuilt nv5600 (I think it was from pheonix remanufactured transmitions?) in my 98 12valve. 3rd gear grinds any time you use it. If your driveing and up shift or down shift to it or if your sitting still clutch and try to put it in third. The only time it dosent is if your sitting still clutch put it in another gear then third. Any ideas what this is? I'm guessing allready whatever it is its going to be $$$$ but really, is it bad install on syncros or something?
any help greatly apprciated

Thanks again
chris

 

Probably why they are so cheap! Only really bad parts get replaced.

 

well the guy who I bought it from (on ebay bad move) sent me a copy of his invoice for the trans. he paid like 4300$ for it.

 

Hi Captain. I see that you were running a 5'er. The NV5600 6-speed is a different beast. The synchro's need more pause between shifts to mesh speeds. I have found with mine that if I don't completely let off the throttle and keep the revs up a bit it shifts much better. In the colder temps it doesn't easily go into fourth either so I use the same technique and it helps avoid the grinding. I hope this helps. Maybe someone will chime in with other suggestions that's had a rebiuld issue. I also know that Dodge had service bulletins on this matter.

 

I just find it odd that its only third gear. even sitting still not moving I cant shift into third without it grinding.

 

That is odd. Mine doesn't like to go into any gear unless I let off the brake and then re try, but it doesn't grind. I've read threads regarding the synchro's and that usually the 2nd-3rd one is commonly the first to go. I also just read a thread on the Southbend clutch install with shifting probs and the suggestion was to check the master cylinder for fluid level or air in it. Lookk in 2nd gen engine driveline for that one. KM

 

It was titled "SouthBend Clutch Problem" in 2nd Gen Engine/Drivetrain.

 

I called blumenthals. apprently thats the place to go to if you need a rebuild on a 5600. The manual guy wasnt there but the automatic guy said right away that its a third gear syncro. I'm sure the rebuild is going to be big bucks let alone shipping 2 ways from PA to Ok. Has anyone ever done syncros in a 5600? Would it be impossable to change out just the third one in my driveway/garage?

 

me and one of my dads friends (a bone-a-fide) big rig guy, took mine down, and put syncros and bearings in mine (the first time it went down), and he said that he would never take down another 5600, and he works on big rig trannys all the time. come to think of it 3rd is on the bottom shaft, and it takes a 40 ton press to get it apart. long story short NO you can't

 

Not in your driveway but tear it down as far as you can then take it to your local trans shop and have them press it off and back on with the new parts.

 

short term you can try double clutching it. does not fix but may keep it from grinding
Clark

 

double clutching seems to reduce the grinding but dosent stop it completely. I'm afraid of damanging it even more. So much for a "new" transmition. Right now I'm just flogging it in 2nd and going right to 4th. Also what can you guys tell me about the diffrent versions? I read something on here about a DEE or something that was suposed to have been setup for better oiling and smoother shifting that makes the syncros last longer in 2002. If im sending this out to be done again at what will probbaly be the same cost as what I paid for it maybe they can do any updates to it too.
thanks
chris

 

The one problem with that is, he would be in the same boat as he is now (no warrenty) tring to save a $100

 

What fluid are you running in it?

MikeyB

 

syncromesh. So after I put my DDP4's intoday (deffintly dosent seem like much of a power increase, maybe its because I stil have a 12 plate?) I went for another short ride. I was able to double clutch and get it to go into third without grinding. Still cant downshift though.