Ok, sticking with the original premise:

First we must determine exactly how the Germans managed to achieve victory and what they gained in doing so. It is clear that if Germany gets involved in the Soviet Union with Britain not defeated they lose. Getting the US involved as well only seals the certainty of this occuring.
Therefore, the most likely scenario for a German victory is that with the fall of France the Germans manage to bring England to the negotiating table. I would postulate this is done by focusing on a defeat of Britain in North Africa and by ramping up both the bomber campaign and U-boat war.
Given these conditions say by 1943 the war is ended with Britain negotiating a peace with Germany. Germany, having little interest in Africa abandons it to Italy and local governments friendly to Germany. This leaves the Germans with essentially Europe except Britain.

Post war, the Germans prepare for a go at the Soviets. They also begin to consolidate their position in occupied countries. Hitler proceeds with the Holocaust against all of occupied Europe. Much of the German war economy is scaled back to keep the civilian population complacent. This means many of the more far fetched and long term military research programs are cut back severely or eliminated. Rocket research is scaled back as is jet technology. Nuclear research is nearly forbidden as the Nazis view it as "jewish" and not in keeping with their political beliefs.
In armor a slightly improved model of the Pz IV is introduced (something like the VK 3001 or 3501) but nothing like the Pather or Tiger appears (there would be no reason for either to be built without facing the T 34 or KV 1).

Elsewhere, the US still crushes Japan and comes out of that war with the most powerful navy and air force on the planet. With no war in Europe, the US returns to a more isolated political stance once again. But, the US also finishes their nuclear weapons program in secret never having actually used a bomb. The Soviets also embark on a nuclear weapons program based on esponage of the US program. The US also continues to develop some missile technology and adopts jets from the British.
The isolated Germans (Nazi Europe would be xenophobic to a great degree) fail to see many of these developments until they are behind the curve in technology and then must play catch up.
By the late 40's or early 50's the Germans have a go at the Soviets only to find they too have nuclear weapons. This comes as an utter shock to the Germans who are decades away from their own bomb. The US provides the Soviets with material support. A stalemate ensues with both nations fighting a pointless blood bath. This time it ends with both exhausted and a negotiated peace.
In the long run....ie into the 60's it becomes a matter of which dictatorship fails first.