mattn124

Hello;

The truck in my sig has a weird transmission leak. I have the nv4500 5-speed manual transmission.

Appears to be leaking between the transmission and the transfer case. In fact, I checked today and I think some of this fluid might actually be making its way inside the t-case as it was overfull and looked a little dirty.

Here is where I need advice:

1. Am I correct that there is a seal on the output of the nv4500 and also a seal on the input of the t-case?

2. If I take this all apart to replace seals, is this a good time to perform any of the "5th gear" upgrades?

My truck currently does go into and stay in 5th gear; but does take a little effort at times. Also, I will always have a slight grind going into reverse if I don't first move the shifter to 1st gear before moving over to reverse.

I don't want to just throw a bunch of money on a 5th gear fix if I don't need to, but if it will save me some headaches down the road; I might as well make the improvement while I've got it all apart.

Thanks in advance for any and all replies.

--Matt

patdaly

Been a while, but I believe the only seal is on the input of the Transfer Case.

I am probably the worst guy to ask about 5th gear fix, because the only thing I found that lasted with the way I lug mine is the splined external retainer.

That being said, if you haven't lost it yet, you probably won't. I would be tempted to just drop the transfer case and address the seal issue.

KATOOM

There is an output seal on the transmission and an input seal on the transfer case. The two do not share fluids and the space between is supposed to remain dry. The 4500 uses a specific 75-80 gear oil and the transfer case uses ATF+4. That said, many (like me) use Dextron III.

I agree that I'm not sure I'd mess with the 5th gear unless you needed to. But as long as you're in there its not a bad idea to be proactive. Although I'm not sure I'd change the nut but rather I've heard lots of good things about this product (here) which is supposed to be one of the better solutions if its installed correctly.

Unfortunately the updated nuts arent much help and the replacement fully splinned gear shafts are now low quality metallurgy garbage made in China which are weaker than the partial splined OEM shaft.

Lastly, if you're grinding any gears or having trouble getting into gear then check the fluid to make sure of its condition, level, and type. And check the master/slave hydraulics to see if they're potentially bleeding down which would cause incorrect clutch fork throw and partial engagement. If the hydraulics are fine then you could have a dragging pilot bearing. Nonetheless, NEVER EVER force it into gear or you'll destroy the carbon composite lined syncros. Very expensive.

mattn124

Thank you both for your input.

Katoom,

I also nun dexron, and I only use the Chrysler/mopar fluid inside the nv4500. I know some guys like various aftermarket stuff, but I just stick with the factory flavor.

Thanks for confirming about both oil seals. Are there also any gaskets in between any of those components?

I looked at the repair site you listed and plan to call them tomorrow to ask for prices.

Also, installed the upgraded clutch hydraulics from South Bend at the same time i put in a clutch from them,, roughly 15,000 miles ago. All seems fine in that regard, but if I want to check, how do I check them for bleed down? On the topic of a dragging pilot bearing, I really don't want to take the transmission out again, so I'll hope that's not it....

Lastly, I never have to force it in gear. I have just noticed, over time, that she goes into reverse real easy everytime if I put it in first gear position before moving to reverse. I'm talking about all during the same clutch-pedal -press action. If I don't do this, it will still go right into reverse, but I just get a chirp or a minor gear grind when I do.

Does the fact that it goes into R easier when I do this move to first gear mean I might be in for a rebuild soon? I'd hate to tear it all apart for replacing seals only to take it apart again for a transmission swap....

Thanks again for your input.

-Matt

KATOOM

If you have Southbend parts then by all means give them a call and exhaust their customer service..... But more than likely its not the pilot bearing because their larger sealed roller pilot is far superior to the open needle design.

The way you can test for a master/slave not holding pressure is by parking on a solid flat surface with the e-brake off. Then holding the clutch pedal in for around a minute, eventually starting the truck in gear. If the truck wants to try and move in gear then the hydraulics are bleeding off pressure and allowing the clutch to re-engage.

But again, SB should have a better understanding and input as to what things to look for in regards to possibly why the clutch isnt fully disengaging which may or may not be causing clutch drag.

I had a problem with my SB clutch in that the throwout bearing was not rolling smoothly and also sticking as it moved along the input shaft (propeller shaft) of the transmission, which all resulted in a sticky clutch pedal, chatter upon engagement, and difficult to get in gear from a stop. I took out the OEM replica throwout bearing they supplied and replaced it with a SKF throwout bearing and everything works very smoothly.

Or.....maybe its just your transmission showing its age.