Need some input please. DEAD nv4500.


My truck with 113000 miles has an nv4500 with the stock clutch. I was towing a 73' dodge demon to new york yesterday, and all was well until the 6 mile hill. Keeping a constant speed of 65mph the egts stayed around 1000 degrees at 20psi. Well to say the least I got about 7/8 the way up the hill and my tranny let go. Stuck in gear and may have finally fried the clutch as well.

Now its time for either a rebuild or a swap. Would i be better off rebuilding the nv4500 or converting to a nv5600. I would plan on fixing the 5th gear nut problem (which is probably what went) and put in a 1 3/8 input shaft in the nv4500. But I heard you can also have problems with the tailshaft as well.

Let me know what you think please. Thank you

 

I'd stick with the 4500. The 4500 is a simpler tranny, is easy to rebuild and much cheaper to repair.

Okay so both trannies have their issues...the 5600 eats bearings on the mainshaft and destroys 5th and 6th gear, repair parts are not easily available, and is a complete b*tch to rebuild, and very costly to repair.
I guess the best term here would be 'pick your poison'.
I've had both and greatly prefer the 4500.

 

G56 six speed dont waist your time or money on out dated trans.

 

Stay with the 4500, to swap into a 5600 you will have to change flywheel, clutch, transfer case, and driveshafts, it will cost you over 4 grands.

You can get an excellent rebuilt 4500 for $ 1200, it will be taken care of the 5th gear problem too, let me know if you want the address.

Don't go G56, it will cost more than swapping with 5600 and will last less.

 

g56's bite dont go that way. kep the 45 and beef it up. i had both the 45 and 56 behind a 12v the 45 seemed better

 

I was already planning on doing a 13" clutch upgrade on the 4500 hundred anyway. So the extra cost for that i was planning on. I was informed that the 5600 was a stronger tranny, but was also aware of the how rare and expensive they are. I am planning in the near future to be putting down some pretty good numbers hopefully around 500hp and 1100lbs. Just want to make sure I only have to do it once and not kick myself for doing the wrong thing.

Does anyone have or has done a conversion who can throw out some input? Differences? which tranny you like better?

Thank you for the advice

Thank you Valv i will keep that in mind

 

If it was just the 5th gear nut that backed off, thats a easy fix for now. Also a rebuild on a nv4500 is much cheaper than a nv5600. So another vote for rebuilding the 4500

 

make sure you get the larger input shaft, was breaking the input shaft gears on mine and was never over 425hp

 

I agree with Box5,it is much cheaper to rebuild a nv4500 then it is to rebuild a nv5600.

Another vote for the 4500.

 

I don't think they are a problem anymore, I just bought a new one and they had plenty of the shelf. $ 2900 for it. Send me a PM, I cannot tell you where I've got it since others are calling me a "vendor". You know, some people.....

 

You might want to pull the tranny out before you make your decision....


Usually when 5th gear fails the nut slips off and and the tranny free wheels, in 5th. Your problem sounds like your clutch or pilot bearing may have failed and has the tranny bound up, the pilot bearing failure is quite common in these. When my pilot bearing started acting up my truck would get stuck in 1st, 2nd, and reverse but acted fine everywhere else.


If you do have to get a new tranny I would stick with the 4500... Plenty strong enough if built properly, much cheaper to fix, the aftermeket has pretty much eliminated the 5th gear problems, and you don't have to mess with any conversion stuff, but thats JMO.

If you want a good 4500 I recomend http://www.standardtransmission.com/
They build a tough 4500, with fully spiled mainshaft to fix 5th. I personally know someone who put 800hp through one of their tranny's for several years and probably close to 1000 dyno pulls without one problem.

....Josh

 

So you guys talked me into it I will rebuild the 4500. That is of course until I can find a G56 to swap.

My plans are to upgrade to a 1 3/8 input shaft, fully splined mainshaft, and possibly the 3250 dd clutch from SB. Hopefully everything else is kosher and can be left alone.

Any ideas on the SB clutch. A few people said this clutch is Awesome, and you dont need to change the hydrolics.

Any ideas?

I will be dropping the tranny this weekend, and swapping with my bros 4500 until mine is rebuilt. I will be sure to keep you posted on what exactly went wrong.

 

The 94-97 hydraulics seem a little beefier than the 98+later units, so I wouldn't worry about it right now.