Make sure to put the check valve back on the correct way.
You may just have a pin hole in a hose.
Had a hard hose under hood brake and I just made a splice.

You said the truck is 2000 model so hoses are 14 years old.
Look for brittle or rough hose condition on the outside of each vac hose and replace the one that need it.
I had hoses that were held together by spiderwebs.
Since you said the cruise was slow to engage

 

I changed the ac/heater control assembly and it fix the problem. Thanks a lot I appreciate the help.

 

Glad you got it fixed. Question, did you get a new one or from a junkyard?

 

Junkyard...$40

 

Good deal!

 

$40? I've been wanting a new one just because the light bulbs are burnt out on mine! Send me your old one and I'll make one good one, lol. Looks like I'm controlling mine blind at night forever now

Chad - 03 Dakota Sport Quad Cab, 01 Durango R/T, 98 Ram Quad Cab