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With only a few test miles on a fresh rebuild ,the first few times out were great.Now it does have. Slow leak when it sits ,I just got it out for a quick drive and noticed it was low on fluid.I topped off the fluid which was about 3 quarts low.It is slipping from a dead stop,fwd and in reverse.Also it doesn't start in low gear when it is in hug gear and doesn't down shift.Is there an adjustment or something that I need to check?

A couple of things. Can you see a leaking spot? Just sitting, fluid will be high in trans and above pan top because the converter drains back when engine is stopped. Maybe a leak is from a pan gasket or a seal on the throttle or selector shaft which would be submerged. The pan holes deform if bolts were tightened too much so if you did not use a straightedge and level the bolt holes in the pan before you reinstalled it that is one frequent source of leaks. Also the shaft seals are prone to leak if the shafts are scratched or you did not replace the seals.

If it is a regular Ultra it does not shift between low and high so will not start in low range unless you specifically place the lever in L. Lever in H starts in high range, stays there and makes one "upshift" to direct drive between 20mph and 45 or so depending on throttle. Lever in L starts and stays in low but still does the direct drive "shift".

How involved was the rebuild? Did the bushings and any worn shafts get replaced? Those are critical items in an Ultra because many of the hydraulic feeds between components rely on passages in rotating shafts. Bushings and good condition shafts are necessary to keep the pressure in a circuit. There are rubber piston rings in the actuators. If those were not replaced and one is leaking that could cause issues.

Is the reverse band adjusted properly? Unless there is a problem with the actuator there is not much to fail in reverse. An anchor pin is known to fail in the Gear Start or Twin Ultras but don't believe that is a problem in regular Ultras. On some bands a strut can fall out if the band is too loose. Usually those are attached and stay in position but is something to consider. If it did fall out there would be no reverse at all. Otherwise, If the adjustment is within range, the actuator piston clamps the band tightly around the planetary and leaves it there until the lever is placed in a drive position.

The throttle adjustment is critical on Ultras in controlling the slip. It determines how much pressure is applied to the high range clutch to squeeze the discs together and also determines when the upshift and downshift happens. There is also no downshift if going over 45 mph. Below 45 a solid tromp of the accelerator to the floor should make direct drive drop out and you will be in whatever range H or L that is selected by the lever. Make sure you follow the instructions to adjust the throttle linkage and also that the lever on side of trans is oriented properly. It points up, not down.

All good points from Howard. I will also ad, how did the builder set the control valve on the valve body? As Howard pointed out the pressure and position is critical. If the Land was not set properly to 5/16" your pressures will not be correct at the correct points.

Also something to consider, was new clutches installed? The original clutches have a slight cup to them. The new aftermarket clutches are completely flat. new clutches leaves excessive slop in the clutch packs and thus takes the clutch piston longer to react as it has to take up the excess slack. Several of us Ultra builders add extra steels and or clutches to take up the slack. You want to get as little space in there as possible for quicker lock up.

Thanks to both of you ,the clutch discs were replaced,the rebuild was extensive,I do remember gutting it to nothing,I was worried about it before the build due to it having a groan when going in to direct drive.Hanks for the advice,I'll check all of this out tomorrow