Engine/Transmission (1994 - 1998) Intermittent hard shifting into 4H, grinding

[JeffP]

Newbie to the forum (Dodge 2500 Diesel 4WD 1996). I'm having intermittent problems shifting into four wheel drive high while driving. When I'm stopped it shifts fine into both low and high. The last time I tried to shift into 4H I let up on the "gas" pedal and pulled back. It was very hard but did finally go in. Sometimes it grinds and "clunks" when going in while driving (around 40-55 MPH). The temperature at the time was around 20 degrees. I know in the owners manual it states that in cold weather you have to stop to shift. If this is my problem is there any after market fixes to this issue. Thanks, Jeff.

 

[JSienkowski]

Last I knew engaging 4WD at any speed above 25 mph was asking for trouble. Basically your transfer case is like a transmission without synchros'-the gizmos that allow you to shift a manual transmission with out "Double Clutching", so basically you are trying to force a "square cut" gear to mesh-hence the grinding. My advise, slow down and smell the roses and things will work perfectly. Oh, when you shift into 4 Low, be stopped and have the transmission in neutral.

 

[JeffP]

I've heard that before from other people also. But I looked in the owners manual and it states that you can shift into four wheel drive high "at any legal highway speed. " I was also hoping that maybe there would be some after market change I can make to allow it to shift better in the cold, after all I use mine mostly in the snow. Thanks for your opinion.

 

[GHansen]

Make sure tire size is the same and pressure is even. Also, check transfer case lube for contamination and correct type.

 

[TurboFan]

Hi Jeff,



Unless I'm really slow and in a hurry, I usually pull back on the selector untill I feel firm resistance then I give it a moment before going the rest of the way. That gives the t-case time to spin up the front driveline before the gears try to engage (to my way of thinking). That's just my thing, fwiw.



If you want an actual fix, there is a kit you can get from a TDR member that gives you the ability to control the front end engagement "manually".

As you know, two things have to engage when you select 4x4. The transfer case spins up the driveline and engages the gear, and the tcase operates a pneumatic valve that through a vacuum operated servo, engages the front axle.



The kit(s) allow you the option to have the front axle engaged even with the selector in 2wd. That way the driveline is spinning so when you select 4x4, no meshing has to happen. As long as your wheels aren't spinning, everything is going the same speed and it goes in easily.



There are kits that alter the existing vacuum operated system, and there are kits that replace the vac system with a cable operated unit.



Bob V is the TDR member with the vacuum kit that I think I will pick up.



Good luck,



Greg