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Discussion Starter · #1 ·
Sorry if this has been covered before but I could not find the clarification I was looking for in the archives.

Could any of you please share your experience/input on this? After installing a non-baffled deep aluminum transmission pan(extra 2 qt capacity) with extension and Allison brass screen filter with non-synthetic Dex/Merc, I'm experiencing sluggish WOT 1-2 shifts in drive after launch with my TH400(no shift kit). 1-2 shifts take a little over a second now with no tire barking. Transmission seems to be "searching" for second gear. Fluid level measures within "full" on dipstick. Car is mild performance build, 4000 lbs, 3:08 gear, converter flashes to 2800 rpm, 1.8 60 foot time & 12.8 ETs. I've seen where some utilize one extra quart with deep pans and some using one pint below full. I'm wondering if fluid level needs to be experimented with now. Is there any generally accepted rationale for fluid levels when using a deep pan such as mine? Thank you.
 

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Hates: Liver. Loves: Diesel
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First thing I would check is that there isn't an air leak. Might have nicked the o-ring putting it back in the case, or not quite sealed on the extension.
 

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As long as the filter stays covered in fluid, the trans doesn't care too much. Just bolting on a deeper pan with the extension and new filter should not have had any impact on shift quality. I am assuming that non-synthetic Dex/Merc was the fluid of choice previously and that we are reading the full mark with the transmission hot. And if you were going after a performance improvement as far as fluid is concerned I would have made the move to either a conventional or synthetic F-Type. Did you remove the plastic tube that the filter is attached too? And if you did, did you put two (2) o-rings on it and make sure it was fully seated in the transmission before putting the new filter on? A second o-ring is a minor upgrade to improve the suction ability of the transmission pump.
 

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Discussion Starter · #4 ·
Yep I double o-ringed and used the AC Delco plastic extended filter tube. Level was checked in park and running after driving 30 minutes at full operating temperature. I will drop the pan and re-check o-rings and tube. I did use non-synthetic Dex/Merc previously and will consider one of the synthetic Type-Fs like ATI's Super F 20WT. Thank you both.
 

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Hates: Liver. Loves: Diesel
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Obviously not Brian's first rodeo, but I have had this happen (rarely) that somewhere there was a bubble. Is it consistent, or did you experience it once or twice and then park it?
 

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Discussion Starter · #6 ·
It is consistent at WOT Curtis. It drives nicely just cruising around town. Now I'm thinking something must be amok with the o-rings, tube, or filter.
 

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Discussion Starter · #7 ·
Update: After dropping pan and inspecting the 2 o-rings, pick-up tube, and filter, all looked perfect. I suspect an issue possibly unrelated to the deep pan install manifested itself at the same time. Coincidence perhaps? I'll now troubleshoot from the converter, transmission, back to the governor. Will likely take a while with workload and holidays approaching. If I can confirm anything, I'll post findings here. Thank you all for your input.
 

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Discussion Starter · #10 · (Edited)
Follow-Up: After going through a checklist in my mind, I kept thinking that this issue has got to be something simple. I got to thinking and on a hunch, I removed the vacuum modulator and valve. I didn't realize it but there was a small spring on the VM valve leftover from a previous shift kit. I removed it and the transmission began performing like normal and barking the tires on the 1-2 upshift. I should have checked that myself and now apologize for taking up everyone's time on this issue.
 
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