4Lw Working 4Hi Not. Any Sugestions

[jason]

I got a 1986 comanche 2.8. Stock. 5 speed. Runs great. Goes into 2wd and 4 wheel low fine but when it goes into 4 wd hi its like its still in neutral. Any sugestions. Like linkage or somethin internal.

[Pete M]

hopefully it's just out of alignment and it's nothing serious. :thumbsup:

 

[cruiser54]

Shifting like this?

 

Here's how the factory suggests you shift the transfer case and I've been doing this since these things were new and I worked at the dealership. Quoted from the owner's manual.

 

"To engage, shift the transfer case lever from 2H to 4H while the vehicle is moving at any legal speed". I let off the gas, throw the lever, and then tap the gas and let off. 

 

4L position: " To engage, slow the vehicle to 2-3 MPH , shift the transmission to Neutral, then shift the transfer lever to the right and pull firmly rearward to 4L". 

[87manche1]

Hate to tell ya probably internal. Had 1 do that to me but I lost 2wd also. Take the plug out and drain it check for metal shavings /parts

[jason]

K thanks for the comments. Will definatley b checkn it out. As soon as the weather gets above the single didgets a little. Thanks for the help.

[carnuck]

Sounds like the viscous coupler is gone (if it's NP229) Or the front diff isn't engaged (if it's NP228)

[cruiser54]

Sounds like the viscous coupler is gone (if it's NP229) Or the front diff isn't engaged (if it's NP228)

But it goes into 4L......

[carnuck]

4 low isn't coupled. The carrier that the planetary of the 228 or the viscous coupler of the 229 is bypassed when it goes into low range. 219 has a variable front to rear in low range unless the Edrive switch is engaged but it was gone before XJs and MJs came out. '87 was the last year the little Jeeps got 228/229 as well but the Full Size Jeeps (FSJs) kept the NP229 till the end. They also had NP208 as a cheap option. It's the bigger, stronger brother to the NP207. All the FSJ cases '80 up are 23 spline and driver's side drop.

 

AMC Eagle used similar cases with no low range NP119 80-81, NP129 '82 to '88 with NP128 in '86 as a "cheaper" replacement because the viscous coupler was so expensive. Even now used ones can command about $500 but no-one has bought the 2 I have for sale. (Ebay is next)

 

If you pull the drain plug and black goop drips out, it's most likely a NP129 and the silicone "oil" acts like liquid sand on the internals of the transfercase.

 

 

If he crawls underneath and looks at the driveshafts while it's going nowhere in 4 hi, the front shaft will be spinning (NP228) or if nothing, the viscous coupler of the NP229 is toast. Once in a blue moon the planetary of NP228s get lunched but that's generally caused by 2 different ratio axles being used.

 

for more fun

http://oljeep.com/edge_tcase.html

 

The ONLY difference between NP228 and NP229 is planetary vs viscous coupler.

 

If the front shaft spins, just permanently engage the front vacuum diff and you should be fine.