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electronic 4x4 shifting problems

Yukoner

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Yukoner Enthusiast

Yukoner

Posted
Posted

Sorry guys if this is a repeat, I did try the search for quite a while.

Anyways have a 2005 2500 HD with pushbutton electronic shift for 4x4 which gives a real whirr and grind while shiftin on the fly? Is this common? Have had a trans sevice done and truck is at 40k so want to solve this while on warranty. Manual says I should be able to shift at any speed. Last time I tried it it would not find any gear.

Anyone else with this problem? Any suggestions as to what to look for? :tear:

mmmikkke Senior Enthusiast

mmmikkke

Posted
Posted
Sorry guys if this is a repeat, I did try the search for quite a while.

Anyways have a 2005 2500 HD with pushbutton electronic shift for 4x4 which gives a real whirr and grind while shiftin on the fly? Is this common? Have had a trans sevice done and truck is at 40k so want to solve this while on warranty. Manual says I should be able to shift at any speed. Last time I tried it it would not find any gear.

Anyone else with this problem? Any suggestions as to what to look for? :tear:

 

 

 

Yeah, but only between 4hi and 2hi.

 

Just in case that's not what you're trying...if you're going through N on the way to 4lo...sparks will fly inside your transfer case and it might get busted up pretty bad.

Yukoner Enthusiast

Yukoner

Posted
  • Author
Posted
Sorry guys if this is a repeat, I did try the search for quite a while.

Anyways have a 2005 2500 HD with pushbutton electronic shift for 4x4 which gives a real whirr and grind while shiftin on the fly? Is this common? Have had a trans sevice done and truck is at 40k so want to solve this while on warranty. Manual says I should be able to shift at any speed. Last time I tried it it would not find any gear.

Anyone else with this problem? Any suggestions as to what to look for? :tear:

 

 

 

Yeah, but only between 4hi and 2hi.

 

Just in case that's not what you're trying...if you're going through N on the way to 4lo...sparks will fly inside your transfer case and it might get busted up pretty bad.

 

 

 

 

Yukoner Enthusiast

Yukoner

Posted
  • Author
Posted

Thanks, Mike. Yeah, I know to stop to shift to 4 low.

So are you saying it's common to get the whirr going from 2h to 4h shifting at any speed?

bummed-n-Md Enthusiast

bummed-n-Md

Posted
Posted

my '02 shifts with no problem. It simply engages. No whirr that I ave ever heard.

 

I push the button (always below 50 mph, typically 25 or less) and it clicks right in. I figure if I am going to need 4x4 I will know it before I get going too fast.

 

I disengage at many different speeds depending on road conditions. (any where btwn 10 and 50).

 

bummed.

mmmikkke Senior Enthusiast

mmmikkke

Posted
Posted

I'm wondering if maybe your front diff is not engaging first, so your transfer case has to start the front driveshaft turning from a complete stop.

 

It should be mostly silent to engage 4HI from 2HI. Maybe a clunk but definitely no grinding or whirring.

Yukoner Enthusiast

Yukoner

Posted
  • Author
Posted

No problem engaging while stopped, no problem disengaging at all.

I suspect you might be on to something Mike.

Bummed I do know in most cases when I will need to get er in to 4 wheel, so should be able to stop and do so. Have not tried any high speed attempts and nor do I want to. Really only needed it once this past winter bringing the fifth wheel home up the Alaska Hwy, hit some late spring snow and slippery conditions and was very nice to have.....no problems :tear:

dewfpo Senior Enthusiast

dewfpo

Posted
Posted
Yeah, but only between 4hi and 2hi. 

 

Just in case that's not what you're trying...if you're going through N on the way to 4lo...sparks will fly inside your transfer case and it might get busted up pretty bad.

 

 

 

 

 

I'd like to think the software would prevent a problem.

 

About 10 years ago we were looking at some property in rural Colorado and the prissy real estate agent drove me across the property and promply got stuck in an irrigation ditch with her new prissy Ford Explorer. She apparently owned this 4wd but had never put it in 4wd since I had to show her how to push the 4HI 'button' and we easily got out of the ditch. When we were done and she was back on the highway I realized she still had it in 4HI so I suggested she push the 2HI button. Well, you guessed it...... at about 55 mph she hit the 4LO button. I yelled "NNNNNNOOOOOOOOOO!!!!!! and grabbed my ears, prepared myself for a loud bang, expected the Explorer to jump up in the air and come to a grinding halt. But nothing happened. They made the 4LO switch idiot proof. And this was back in 95 or 96.

 

So I hope our trucks are protected by similar 'idiot proof software.

 

But I'm not going to try it out.

 

DEWFPO

Yukoner Enthusiast

Yukoner

Posted
  • Author
Posted

Found out from the dealer today, the transfer case is missing a retaining clip, so this truck must never have shifted properly since new.

Will take a day or so to bring the part in, all covered under warranty, including a rental for a couple days. Glad to catch this now and not later....

Thanks for all the comments and suggestions. :lol:

snoman Senior Enthusiast

snoman

Posted
Posted
I'm wondering if maybe your front diff is not engaging first, so your transfer case has to start the front driveshaft turning from a complete stop.

 

The T case is suppose to engage first anyway because the engaged ment of front axle is through a dog clutch style engagement and it will crunch is not close to equal speed accross joint. Some model Tcases use a syncronizer to speed up and engage Tcase front output that can make some noise sometimes while others use a internal electric clutch to engage front output shaft. If it is making a lot of noise those it is not right. Does the noise go away after engagement or stay?

Yukoner Enthusiast

Yukoner

Posted
  • Author
Posted

Noise goes away after engagement, although I have only tried it three times while moving at various speeds, last time it stayed out of gear, I stopped and went back to two wheel drive and called the dealer. I thought at first there was a difference in electronic (two button) and auto shift (three button) but the manual says will "shift at any speed".

I bought this truck with 34k on it just like new but the previous owner prolly hadn't needed to do much 4x4 ing. I have it cause I need it.

Anyways, the GM dealer seems to have it figured, thanks guys.

icecoldtexan Enthusiast

icecoldtexan

Posted
Posted
No problem engaging while stopped, no problem disengaging at all.

I suspect you might be on to something Mike.

Bummed I do know in most cases when I will need to get er in to 4 wheel, so should be able to stop and do so. Have not tried any high speed attempts and nor do I want to. Really only needed it once this past winter bringing the fifth wheel home up the Alaska Hwy, hit some late spring snow and slippery conditions and was very nice to have.....no problems :cheers:

 

 

 

 

 

I was going about 80 mph down the freeway with a friend and he dared me to hit the 4wd button, I was going to fake like I pressed it but actually did. Scared the sh*t out of me, but to my suprise it just went into 4wd hi with just the normal clunk of the front diff engaging. Haven't tried that since.

icecoldtexan Enthusiast

icecoldtexan

Posted
Posted

Yeah, but only between 4hi and 2hi. 

 

Just in case that's not what you're trying...if you're going through N on the way to 4lo...sparks will fly inside your transfer case and it might get busted up pretty bad.

 

 

 

 

 

I'd like to think the software would prevent a problem.

 

About 10 years ago we were looking at some property in rural Colorado and the prissy real estate agent drove me across the property and promply got stuck in an irrigation ditch with her new prissy Ford Explorer. She apparently owned this 4wd but had never put it in 4wd since I had to show her how to push the 4HI 'button' and we easily got out of the ditch. When we were done and she was back on the highway I realized she still had it in 4HI so I suggested she push the 2HI button. Well, you guessed it...... at about 55 mph she hit the 4LO button. I yelled "NNNNNNOOOOOOOOOO!!!!!! and grabbed my ears, prepared myself for a loud bang, expected the Explorer to jump up in the air and come to a grinding halt. But nothing happened. They made the 4LO switch idiot proof. And this was back in 95 or 96.

 

So I hope our trucks are protected by similar 'idiot proof software.

 

But I'm not going to try it out.

 

DEWFPO

 

 

 

 

 

I have pressed the 4wd lo going 30mph and it just blinked a couple times then went into 4wd hi, they did idiot proof them.

Shaners Senior Enthusiast

Shaners

Posted
Posted

Not that it is totally releveant to your situation, but in my '01 2500HD I had to have the whole transfer case replaced @ 4K miles because of a hard (pushbutton) engagement... The truck was in the shop for 2 weeks over this, and a factory rep was brought in because they couldn't find the problem... ended up being an undersized machined shaft.

Yukoner Enthusiast

Yukoner

Posted
  • Author
Posted
Not that it is totally releveant to your situation, but in my '01 2500HD I had to have the whole transfer case replaced @ 4K miles because of a hard (pushbutton) engagement...  The truck was in the shop for 2 weeks over this, and a factory rep was brought in because they couldn't find the problem...  ended up being an undersized machined shaft.

 

 

 

Well Shane, Mine is still in the shop, waiting for a new transfer case from Wichita. I have been without my truck for a week and a half and probly won't have it for the weekend again. They had it out for the third time and it went from "just a missing clip" to twice finding broken parts in the bottom. At least it's covered under warranty, but that doesn't stop you from being bummed.

I've asked for a documented diagnosis from them if they can figure out for sure what it was, and keep it on file for any future problems.

Hope yours was 100% when you got it back. :driving:

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