thrashingcows

Most transmission shops won't use a kit you provide to do a rebuild, so either drop it off and have them rebuild it or if you have the expertise and tools you can do it yourself.

The NP205 can be resealed and gasketed fairly easily, I redid mine a year or so ago since it started leaking pretty bad after almost 10 years since I rebuilt it. I will advise that you put a thin coat of RTV on all the gasket surfaces since the gaskets in the rebuild kits are super thin and after all this time, and thousands of heat cycles your mating surfaces are not going to be factory fresh and flat, but just take one thing off at a time and clean and reseal and then reinstall that part until your done.

Oran

So I just cleaned off the rear of the transfer case today and serviced it. It was definitely low. Only had about 1 qt of fluid in it and it looked lime atf and smelled liked burnt hair. Drained all i could out of it and re filled it with 80w90 gear oil until it started flowing out of the fill port. Took just o er 2 quarts. Went to drive it and while it did shift a little bit better, still couldn't get it out of 4h. Crawled under again to find the linkage and saw so.ethi g that just doesn't seem right.


Can anyone tell me why someone might have tried to glue velcro around that linkage? Can I expect some sort of major problem if I remove both pieces?

oliver foster

I can not see the pictures very well, but that looks like someone stuffed some rubberized membrane between the metal lever and shifter gate, My guess is to try and stop the very common rattle that comes from the 4x4 linkage.

Oran

It's actually velcro, do you think it would be safe to remove it?

oliver foster

It does not look like it is holding anything together from what I can see.

Even if it is.
I doubt taking apart a little velcro is going to make a problem, that, well can't be fixed again with some velcro.

67IHC

Just finished draining the old thicker oil from my Getrag360 and filled it with 5qts of Mobile 1 5W-30 synthetic. Shifts much smoother and so far (aka the quick zip I took around the block to at least get into 4th gear) no noise. None. And no more vibrations.

I want to get it on the highway later tonight to see if that holds up at faster speeds. Suddenly I’m thinking this Getrag 360 has never had the proper oil in it because it’s never preformed this well. And this solution is $70 less than what I was going to buy.

Now the only problem is that it’s so quiet, I can hear all the other things making noise that I need to address.

Appreciate your “old school" wisdom here.

oliver foster

Great to hear.

Ive had good results running Mobil1 5W-30 in a half dozen Getrag shifted trucks, some of them as long at 15 years.

67IHC

Is there a reason that synthetic might work better than conventional oil in these transmissions?

oliver foster

I just figured it would hold up better long term as I do not change it really often, just top it off.

u2slow

Jmho, but i believe synth is a 'stickier' oil, and is usually more temperature stable ( like 5w50 or 0w40 vs 10w30). This also translates into an otherwise thinner oil that protects like a thicker dino oil.

67IHC

Here's another strange advantage of using 5W50 over heavier oils: what used to be a persistent leak at the output shaft has slowed and I think even stopped of late. Bot at all sure how a "thinner" oil could do that, but something changed for the better.

u2slow

Synthetic may have caused the rubber seal to swell/soften.

67IHC

Makes sense. Check again this morning after driving it all yesterday and still no leak. I'll take it as opposed to having to replace the seal.

BearKiller

Way back when these trucks first came out, people were using them like semis because they had never had anything in a 1-ton truck that would actually pull the kinds of loads they were pulling --- and then --- the dealerships had these brand-new trucks piled up behind the service bays waiting on replacement Getrags that were just not there; some did without their new trucks six months or more waiting for a replacement.

The simple reason --- no matter what oil you put in them, original factory fill level was just not enough.

We had a brand-new truck in 1989 and were coming out of South Louisiana up through Mississippi with a 28 x 8 cattle trailer with sixteen big cows averaging 1,700 apiece and it just quit pulling in 5th gear and the transmission was blood-red hot and smoking.

We stopped at a huge Chrysler dealership in Senatobia and the shop foreman showed us something like eighteen trucks sitting there, all with the same problem as we were having and no transmissions to be had anywhere.

After it cooled down, he had one of his guys check the oil level and sent us on our way.

We made it to Kentucky; but just barely; that thing was making terrible noises by the time we got the cows unloaded.


That being said, common advice has always been to remove the fill plug and screw in a 1/2NPT Street El and fill to the top of the elbow with five quarts of 5w-30 Mobil Full Synthetic.

I have pulled some tremendous loads many many miles thus with no problems whatsoever.

Some years ago, I put a short nipple in my street el and welded a "dipstick" in the center of a pipe cap.

I put four quarts in the transmission and cut a "Add One Quart" line on my dipstick.

Then, I poured in the fifth quart and cut a FULL line on the dipstick.

Then, at the Flemingsburg "Meet and Greet", I saw a most intelligent gentleman who had routed a length of see-thru hose from his street-el with a fitting and cap at the top end, under the hood, where one could pour in the Mobil 5w-30 Full Synthetic without ever crawling under the truck.

I employed his idea on the son's truck and it works well; however, I have not yet created a dipstick to work with it.

My intentions have always been to procure myself one of those cable dipsticks from an old cab-over truck and retrofit it to work with the Getrag/hose set-up.

If one had the cable dipstick in hand before, they could custom cut the hose to fit the dipstick instead of making the dipstick fit the hose.

67IHC

Great solution next time I can find enough room to work on the tranny. For now having the right oil in it has been awesome as it's quieter and better preforming than ever.