Auto mode turns on 4x4 mode

[Charlie207]

I found this nugget...

Great info, but are you sure that the 246 is for GMT900s? Everything I'm seeing is that it's for older, pre-2006/7 vehicles.

Based on some digging, (and my RPO sheet) I have the NQH MP3023/3024: https://evopower.ca/mrws/filedriver/MP_Transfer_Cases.pdf

 

[George B]

Great info, but are you sure that the 246 is for GMT900s? Everything I'm seeing is that it's for older, pre-2006/7 vehicles.

It's not but the operation should be similar.

EDIT:
Here are the TC models for the NNBS -



And here is some info -

The Magna Powertrain MP3023/3024 NQH

In last month’s article we discussed two of the three new models of transfer cases from Magna Powertrain, the MP1222/1225/1226 NQG and the MP1625/1626 NQF. This month we will discuss the operation and mechanical functions unique to the MP3023/3024 NQH. Figure 1 breaks down the identification...

www.transmissiondigest.com

Looks to operate about the same to me.

 

[Charlie207]

It's not but the operation should be similar.

I edited my previous post with a link at the same time you posted this... so I replied here to share it.

 

[jwth]

wow I feel so foolish
I have driven my 2003 in auto 4x4 on the e way and in the city for 230,000 miles without replacing the front dif.
not in summer unless heavy rain, but for sure from the beginning of november til may.
no problems and no noises
maybe I should have the dif replaced anyway.

 

[George B]

wow I feel so foolish
I have driven my 2003 in auto 4x4 on the e way and in the city for 230,000 miles without replacing the front dif.
not in summer unless heavy rain, but for sure from the beginning of november til may.
no problems and no noises
maybe I should have the dif replaced anyway.

Can't hurt... It's only money.

 

[Geotrash]

wow I feel so foolish
I have driven my 2003 in auto 4x4 on the e way and in the city for 230,000 miles without replacing the front dif.
not in summer unless heavy rain, but for sure from the beginning of november til may.
no problems and no noises
maybe I should have the dif replaced anyway.

Funny you should say that. 230K is about where the front diff on my 2002 shit the bed. The PO drove it in auto mode for its whole life before selling it to me. Driveline shop told me not to run it in auto mode any more. Lol.

I suspect maybe the problems arise when people run mismatched tires/tire pressures causing the clutch pack to engage more than it otherwise would, wearing out bearings and such faster.

 

[George B]

Like I said earlier the only difference between the AWD and part time case is the passenger side output shaft with the AWD being solid and the part time having a disconnect. Running that differential engaged in itself will not cause an issue.

 

[89Suburban]

 

[Fless]

Like I said earlier the only difference between the AWD and part time case is the passenger side output shaft with the AWD being solid and the part time having a disconnect. Running that differential engaged in itself will not cause an issue.

^^ This. The wheels will roll the diff all the time. The only time it engages with the front propshaft is when the front diff actuator is called for during rear wheel slippage. Hence "AUTO."

 

[tungsten]

He said propshaft.