Pat at Pat's Transmission did the rebuilds. I gave him your name and number yesterday. I drove it yesterday for the first time in 14 months.

My transmission and rear end have been rebuilt. Prior to driving (cool), the transmission will immediately engage when shifted into drive, low and reverse. After driving (warm) there is a delay in engagement until the RPM is brought up slightly. The trans has a full synthetic ATF in it.

What ATF should be used? Any other suggestions?

It looks like 28 29/32". Can you confirm? What is the source document?

The throttle valve relay rod is rather stout and I doubt it would get bent except in extreme cases. What should be the length between the centers of the linkage holes at the opposite ends of the rod? The rod that came with my spare 1952 Ultramatic transmission measures approximately 30 5/8". Is the 1951 rod the same length? See image below.

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Reference "Service Manual Section VII - Ultramatic Drive". "Ultramatic Drive Adjustments - Throttle Valve Lever" (page 27). The adjustment is described there. From that description the shaft must be smooth (not splined). Is that correct? I have a 2498.

I've read that multiple times. I read it again. I believe the valve is shown in its initial position which allows oil to the front pump relief valve. I would have thought that the first exhaust port and the inner spring would have regulated the pressure to the converter inlet valve. I guess the rear pump pressure is so much greater than this regulated front pump pressure such as to overwhelm the first exhaust port and continue to move the valve inward. It makes sense that the flow rate of a liquid through an aperture would have a point of non-linearity verses pressure. I believe the front pump is regulated at 85 and the rear at 93, pretty close. Also, the purpose of the first annular groove is not explained.

I'm wondering how this valve operates. What I don't understand is how the valve operates with only one oil inlet. Does the rear pump simply OVERWHELM the inner spring and the first exhaust port thus moving the valve to engage the outer spring? At this position fluid is routed to the front pump relief valve which idles the front pump. Pressure greater than 93 PSIG exits the front pump exhaust port achieving regulation at 93. What is the purpose of the first annular groove?

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You might want to ask to help determine if you have your car running right.

I'm searching for a rebuilt, usable as-is, rebuildable or NOS differential carrier assembly (pumpkin).

Please let me know if you have one or where I might get one.

3.54 to 1
436831

https://packardinfo.com/xoops/html/mod ... ue=436831&ButtonLookup=Go

1951 200 Ultramatic 3.54 to 1. I replaced the axle bearings and seals. Rear end is noisy.

It has been at the transmission shop for 10 months. The transmission has been rebuilt but the differential carrier assembly hasn't been touched. To try to make some progress I'd prefer to buy a rebuilt differential carrier assembly and just put it in.

I may even get one and try to rebuild it myself.