NV4500 Clutch & Input Shaft Question

[codie2379]

So about this time last year I installed a Valair 13" Upgrade clutch supposed to be rate at 400HP and 900fts torque ( I dont think I'm there but I could be wrong ) and I had zero problems  but maybe 2 months ago I went to pass a line of vehicles and bumped up the Quadzilla up romped on it and slip went the clutch. Now it will slip on any setting except stock when I get on it and progressively has gotten worse. So now I'm looking at going to a dual South Bend but before I drop a grand

1) Anyone know of anything I should try to get the current clutch to heal itself or so to speak cause I dont!?

2) I am thinking about doing the 1.375 input shaft upgrade, is it necessary? What do you really gain?

 

[Mopar1973Man]

Whoa!

 

Before you make another step. What size tires are you running? If your larger than a 31" tire DO NOT do the quick ratio box! Quick ratio box can be used on tires and wheels smaller than 31" inch. If you do install it will cause the box more stress being it too low of a gear ratio to push large tire left and right you need to keep the standard ratio steering box. Again do not opt for "quick ratio steering" unless your stock or smaller. Just the same issue with oversize tires on 3.55 axle gears, making the final ratio too low. Like on my 1996 Dodge I'm running 215's tires (30.6" tires) and could easily upgrade to quick ratio.

 

Being I've reduced to 245's (30.5 Inch) tires I opted for the quick ratio box on my truck. I'm running the Blue Top Steering box. Sad to say I've got a warranty claim on mine and will be pulling it back out for Ryan to look at. At 423k miles I finally blew up my power steering pump. It was a OE pump. Shaft issue and leaking. Ryan is going to take care of it for me. Just mail it back to him.

 

I'm running the Valair dual disc. But here we go with tires. If your tires are large your most likely trapping torque in the driveline which typically creates a slipping clutch problem. You need to look at the tire size and look at the final ratio to the ground. For example I drop from 265's to 245's tires with 3.55 gear creates a final ratio to the ground at 3.69:1. 

 

The OPTIMAL final ratio is 3.55 to 3.73 to the ground. 

 

So with just going to 285's from 265's will reduce your final ratio to 3.42:1 ratio adding drag and stress to the clutch. I'm at 500 HP now and never slipped a clutch but I do slip tires which is absolutely fine being the excessive torque burns rubber instead of spinning clutches or breaking driveline stuff. I've already managed to break a mainshaft in a NV4500 at the 3rd / 4th gear on 235's tires (31.7" tires) and Edge Comp (Metal fatigue). Then managed to break the teeth off 5th gear with Quadzilla on 245's (30.5" tires) at 80 MPH on the interstate. (Metal fatigue)

 

 

 

 

Edited November 15, 2020 by Mopar1973Man

[codie2379]

 

 

55 minutes ago, Mopar1973Man said:

Before you make another step. What size tires are you running? If your larger than a 31" tire DO NOT do the quick ratio box! Quick ratio box can be used on tires and wheels smaller than 31" inch. If you do install it will cause the box more stress being it too low of a gear ratio to push large tire left and right you need to keep the standard ratio steering box. Again do not opt for "quick ratio steering" unless your stock or smaller. Just the same issue with oversize tires on 3.55 axle gears, making the final ratio too low. Like on my 1996 Dodge I'm running 215's tires (30.6" tires) and could easily upgrade to quick ratio.

 

Being I've reduced to 245's (30.5 Inch) tires I opted for the quick ratio box on my truck. I'm running the Blue Top Steering box. Sad to say I've got a warranty claim on mine and will be pulling it back out for Ryan to look at. At 423k miles I finally blew up my power steering pump. It was a OE pump. Shaft issue and leaking. Ryan is going to take care of it for me. Just mail it back to him

So you lost here??

 

56 minutes ago, Mopar1973Man said:

'm running the Valair dual disc. But here we go with tires. If your tires are large your most likely trapping torque in the driveline which typically creates a slipping clutch problem. You need to look at the tire size and look at the final ratio to the ground. For example I drop from 265's to 245's tires with 3.55 gear creates a final ratio to the ground at 3.69:1. 

 

The OPTIMAL final ratio is 3.55 to 3.73 to the ground. 

Yes I know you are 100% right I do need to change my gears and I will bite the bullet and do it, is there nothing that you know of to try as far as the clutch? or are you saying when final drive ratio is changed clutch might hold?

Is there a benefit that you know of as far as stress reduction on other parts of the system that you gain when going to the larger input shaft? Thanks for the help

 

[Mopar1973Man]

11 minutes ago, codie2379 said:

Is there a benefit that you know of as far as stress reduction on other parts of the system that you gain when going to the larger input shaft?

 

Never upgraded input shaft. I never broke the input. Still running stock NV4500 input. I broke the main shaft and 5th gear. Hence why I went down in tires to allow it to break free and release the built up torque and spin the tires than hold tight and break stuff more.  

 

11 minutes ago, codie2379 said:

or are you saying when final drive ratio is changed clutch might hold?

 

Yes. It will aid in getting it to hold. Right now your tires are holding back a lot of torque and the weakest point is the clutch so the clutch spin to release the built up torque. So what size are you running? I can calculate the ratio for you and tell you what is needed to correct. Like my old Southbend when I upgraded to +150 HP injectors and figure out the quadzilla tuning now I produce enough power on Level 2 (Stock fuel) to spin on dry pavement. Then I built more power in tuning and spun the clutch. Then upgrade to dual disc Valair. Yeah I produce a lot of power but get nearly all of it to the ground and very little loss in the driveline being my engine oil (<170*F) and trans temp are very low. (<140*F). 

 

11 minutes ago, codie2379 said:

So you lost here??

No I didn't lose anything per se. It was a bad shaft that got a nick in the metal that is ruining my output shaft and was over looked on the build. I knew about it back when it failed the first time but with my daily task of getting @MoparMom to dialysis I just resealed the shaft and told Ryan I would deal with it later. Now later is here winter time and things are slowing down I can send it in for a replacement shaft and new seals. 

 

Again I'm using "Quick Ratio" because I'm running smaller tires. Don't install on oversized. I had a very long discussion with Ryan about this. 

Edited November 15, 2020 by Mopar1973Man

[codie2379]

 

1 hour ago, codie2379 said:

So you lost here??

No I didn't lose anything per se. It was a bad shaft that got a nick in the metal that is ruining my output shaft and was over looked on the build. I knew about it back when it failed the first time but with my daily task of getting @MoparMom to dialysis I just resealed the shaft and told Ryan I would deal with it later. Now later is here winter time and things are slowing down I can send it in for a replacement shaft and new seals. 

 

 

What I meant to say " So you lost me here" meaning I wasn't tieing a power steering gear box together with clutch slippage or input shaft?

 

So when I pull my camper, tractor, hay or anything I put my 245/75/17 on some 3rd gen wheels I have ( if I could grow up! a little more it wouldn't bother me on how it looks and I'd run them all the time ) Just running around I have a set of 285/75/18's which is basically a 35 by 11 ( not practical I know but looks good ) and is in fact what was on when I spun the clutch!!. When I re-gear I was going to go with 4.30 ratio do that seem correct to you? Thanks again I really do value your input

 

But I think 4.10 is the breaking point of being able to use my carrier so if thats the case it will be 4.10s

[Mopar1973Man]

9 minutes ago, codie2379 said:

What I meant to say " So you lost me here" meaning I wasn't tieing a power steering gear box together with clutch slippage or input shaft?

my bad i wasn't totally wake and still hammer my morning coffee.. sorry my bad...

[Dieselfuture]

I'm my opinion if money isn't too tight get a bigger shaft and clutch. Shaft's don't break in normal use but if let's stay you're putting down extra horse power and all the sudden bite traction, that's when carnage happen. My step dad has a 4rner and it has 5.29 axle ratios, running 35"s never had a problem until 1 day crawling up a steep hill on some boulders, one of the tires must have slipped and bit traction, loud pop and ring gear was missing 3 teeth. If you ease into it from the stop and get going then hammer it down, probably don't need anything special, it's the rare occasion that things break. 

I don't think you can do much to the clutch and sounds like you might be pushing more horsepower than your clutch can handle anyhow, might as well put something better in. Not sure what to tell you on dual disc, I believe that's what my truck has( po put it in), it is slow to shift and a little noisy when the tranny is warmed up, but it does grab. Someday I'll need to make a decision on this myself.