Mercon V in place of Mercon in Transfer Case

[awhughes]

I changed the TC fluid today with Castrol mercon v atf. The shifts are not the same. It slips into gear sometimes. I noticed this change immediately with the first test drive. Can anyone else describe ther experience and ill effects of using mercon v in the TC? Where the problems resolved with draining and replacing with plain mercon? Note, no problems of this sort prior to this fluid change.

 

[Glacier991]

Not sure what you mean when you say it slips into gear....the transmission does the shifting....is your 4405 TC an AWD or Control trac ?

 

[awhughes]

The TC is a control Trac. The shifts take longer to engage. Does the TC have much to do with the shifting of the transmission? I need an education (short summary) on what the TC does in conjunction with the tranny. The TC fluid was changed 40k ago. The milege is 164,700 original with no work on either trans or tc other than fluid changes.

 

[Glacier991]

The transfer case, generically, operates to either provide the engine's power through the transmission output to the rear wheels only (4X2) or both the rear and front wheels at the same time (4X4). Shifting between 1st gear, 2nd gear etc, is ALL done by the transmission, not the Transfer case.

In the control trac... we tweak this idea a little...the operation of a control trac is well described in detail in the Borg Warner 4405 Transfer Case Rebuild Diary in the stickies section above.... so I will give the shortened version...

This (control trac version of the Borg Warner 4405) transfer case detects slippage in rear wheels and when it does, it will automatically start channeling more power to the front wheels to overcome the rear wheel loss of traction.... when it recovers it goes back to a more normal rear wheel drive setup. This Transfer case never really does true 4x2... there is always a slight front wheel engagement to a minor degree regardless.

But your shifts are the transmission's doing.