Holes in the transfer case - 2003 GMC Sierra 1500

Dose · August 17, 2020

Hi,

I'm sitting far away in Europe and need some infos / help: I have got little holes in my transfer case. The first one was on the right side (size ~ 0,158" or 4 mm). After repairing it I got a second one with the same size - and viewed from the side it was exactly in line - only a little higher.

So I think, I need a new / remanufactured / reconditioned transfer case. Does anybody knows a reliable dealer?

And of course it would be interesting, what has caused those holes? The last weeks I didn't use the 4WD.

2003 GMC Sierra 1500 / Vortec 5300 / 4WD / Z83 / SLE / Regular Cab / Long Bed

davester · August 17, 2020

This sounds like a case of "gm transfer case pump rub". Google that for the cause, where the problem happens (it rubs through in a specific spot), and fixes for it. It happens even if you never use 4wd.

But double-check that it has rubbed through in the pump-rub spot...

Assuming it is the pump-rub problem, and that you haven't run the transfer case dry so it makes grinding noises, a cheaper fix would be to just replace the rear case half and install a fix for the pump rub problem. Fixes include getting a rear case half made of a different material, billet oil pump, or a pressed metal plate that goes over the pump.

Dose · August 18, 2020

Hello Davester,

many thanks for that explanation and you are right: I havn't used the 4WD often - or to be honest only rarely. But it is making no noises. Anyway, here around in Germany I don't find any mechanic who is able to repair it. And my Haynes Manual is saying that at any rate, the time and money involved in an overhaul is almost sure to exceed the cost of a rebuilt unit. That's why I asked if somebody knows a reliable dealer.

I already found and contacted today www.powertrainproducts.net and www.randyworldwide.com. Now I'm waiting for their answers.

Thanks again

Jürgen

Colossus · August 18, 2020

Ahhh the infamous pump rub on the GMT-800s. Boy does that bring back memories of this forum back in the day. Jurgen, you will need a new or refurbished trasfer case if you wish to have 4WD abilities. Over here in the States, many went with a Jasper rebuilt transfer case, so if you can find something like this over in your neck of the woods or maybe have one shipped to you, that will be your best bet. I hope this is helpful!

https://www.jasperengines.com/transfer-cases

Colossus · August 18, 2020

https://www.dieseltechmag.com/2013/08/what-is-pump-rub

davester · August 19, 2020

If the transfer case isn't making any bad noises, it likely will be cheaper to just replace the rear case half and install a pump rub fix.

Dose · August 19, 2020

Hello Colossus,

many thansk for your infos. A few minutes ago I have already contacted jasperengines and I hope that they ship worldwide - because a lot of US-companies don't do that. And the link to the dieseltechmag is great, the explanation there is really good.

And Davester: I believe you that that could be cheaper. But first I have to find somebody who is able to do that, because I don't trust myself to do that.

Dose · August 20, 2020

Hey Folks,

meanwhile I got two offers, one from the recommended jasperengines (Thanks Colossus) and one from Randys Worldwide. Now I'm sitting here and thinking, because all in all the difference is more than 700 Dollar. Hm...

Regards

Jürgen

txab · August 20, 2020

Nice looking truck. :thumbs:

Dose · August 21, 2020

Thanks!

Colossus · August 22, 2020

Jasper has a good reputation in the automotive repair industry but honestly I do not know anything about Randys.

What kind of pickups are common in Germany? What kind of comments do you get about your Sierra over there? It does look nice!

Dose · August 23, 2020

Hello Ryan,

I did it with Jasper, the deal will be finished tomorrow. They offered me two transfer cases: OE-quality in a Magnesium case and an upgraded Aluminium case. I took the last one.

And according your question: Pickups are not as popular as in your country. The most common pickups are the Ford Ranger and the VW Amarok, followed by Nissan Navara and Toyota Hilux. They all have in common that they are smaller than American pickups - which play a minor role (bit part) on our market. Especially since GM has cancelled their activities on the European market it has become very difficult to get parts. Consequence: A lot of people are selling their GM-products.

We own our Sierra since March 2008 and we are really exotic with it. Dortmund (600.000 inhabitants) is situated in the Ruhr-area - that's one of the five biggest industrial areas in Europe with about 5.1 million people. And in all the years I have seen one (!) GMC Sierra like ours. There are more Silverados of course but with our GMC we are real outsiders.

Regards

Jürgen

On 8/20/2020 at 6:53 PM, Dose said:

Dose · September 25, 2020

Hello Ryan,

meanwhile my GMC is back on the road, the Jasper transfer case is installed and everything works perfect. The picture was taken last week on a camp site in Eastern Germay about 350 miles away from home.

All the details with Jasper and a very kind customer service (Thanks a lot Angie!) have made it very easy for me to order a heavy part like the transfer case from thousands of miles away from the USA.

Insofar thanks to you, Ryan, for your tip.

Regards

Jürgen

SmokChsr · October 13, 2020

There are normally 3 spots where it will wear through. Despite all the laughs, yes JB weld (I think it was called water weld) it's a white epoxy putty, works quite well at buying many months of time. (got one I puttied a year ago and it's still doing fine). The first time this happened to me I got the Jasper rebuild, unfortunately it didn't last as long as the original before it rubbed through. At least in the one I got they put a new plastic rub protector on 2 out of 4 of the pump splines. The plastic protectors came right through the case at the two locations where they put the protectors. Hopefully Jasper is doing better now, but no I wasn't a happy customer. Since then I've purchased the the replacement rear half and replace it on my 06 Tahoe that had the Jasper rebuild. My 05 tahoe still had the JB weld in place waiting until it's cool again so i can replace it's back half.

Of course the key is making sure you get the leak stopped early and making sure the transfer case is kept full of fluid to prevent damage. The cost involved was around $3K for the Jasper installed, vs around $250 for the new rear casing, and 6 hrs labor replacing the case.

Note: when I did the JB weld I cleaned the area involved very well, and used a dremmal tool with a small round stone to get down to bare metal, and made sure it was well de-greased before applying the JB weld.

Dose · October 14, 2020

Hello Alan,

many thanks for your very detailed information and the hint to JB weld . We call it cold welding, and for the first hole in the transfer case I used some thing like that (from the outside). Here in Germany it is Weyers Haftstahl (see attached picture). But after the secondf hole in a week I was afraid that there are more coming. I kept the old transfer case because it was too expensive to send it back as a exchange transfer case (pledge). So in the upcoming winter I will open it and have a carefull look without beeing in any hurry. I keep you informed here in that forum and I will show pictures of what had happend. Thanks again and best regards

Jürgen