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lbear

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Jun 15, 2019
On the Hughes Deep Aluminum trans pan. Can one install either a 2004R or 700R4 trans filter?

Is the 2004R trans filter a "bad" filter? I know it's a top feed vs a bottom feed (700) but the difference in around 1/2" between pickup locations.

Also, is it OK to over-fill a 2004R? What, if anything, can be detrimental if it is overfilled by 1 quart or so?
 
If you over fill too much and the fluid level reaches the spinny bits they'll cavitate the oil into a foam. Oil that's full of air doesn't lubricate and it can't build enough pressure to engage the clutches and you'll burn up the friction materials.

1/2 to 1 qt over top. Max. Checked hot and at idle.

Use the bottom feed 700-R4 filter. The best solution is a pan with a pickup at the bottom, but those seem to be rare and costly.
 
If you over fill too much and the fluid level reaches the spinny bits they'll cavitate the oil into a foam. Oil that's full of air doesn't lubricate and it can't build enough pressure to engage the clutches and you'll burn up the friction materials.

1/2 to 1 qt over top. Max. Checked hot and at idle.

Use the bottom feed 700-R4 filter. The best solution is a pan with a pickup at the bottom, but those seem to be rare and costly.
With op's deep Hughs pan and a 700R filter ,,isnt that a bottom feed setup?
 
With op's deep Hughs pan and a 700R filter ,,isnt that a bottom feed setup?
There are better setups with a pipe and filter that puts the filter way to the rear and bottom for best chance to stay submerged.
The 700r4filter fits under a stock pan but you do need to be aware of the pressure switch in the VB and that a metal filter can ground it causing probs.
 
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I assume the problem is for vehicles that launch really hard with good traction. On a street car with street tires, is this still a problem?

A Hughes deep pan with a 700 filter and 1 quart overfill should be more than adequate for a street car, right?
 
I assume the problem is for vehicles that launch really hard with good traction. On a street car with street tires, is this still a problem?

A Hughes deep pan with a 700 filter and 1 quart overfill should be more than adequate for a street car, right?

The stock pan with the 700 filter and an extra cooler would be a more cost effective move for a near stock street vehicle.

The deep pan provides extra fluid mostly as a heat sink, and a finned deep pan will help suck some heat out of the fluid. But if you're not racing the car, it's not going to matter.
 
The stock pan with the 700 filter and an extra cooler would be a more cost effective move for a near stock street vehicle.

The deep pan provides extra fluid mostly as a heat sink, and a finned deep pan will help suck some heat out of the fluid. But if you're not racing the car, it's not going to matter.

What about "uncovering" the filter on a street car with a Hughes pan and 1 quart overfill? Is it feasible that the filter would be uncovered on a street car with street tires?

What is the ideal trans temp? Under 180F?
 
The stock pan with the 700 filter and an extra cooler would be a more cost effective move for a near stock street vehicle.

The deep pan provides extra fluid mostly as a heat sink, and a finned deep pan will help suck some heat out of the fluid. But if you're not racing the car, it's not going to matter.

What about "uncovering" the filter on a street car with a Hughes pan and 1 quart overfill? Is it feasible that the filter would be uncovered on a street car with street tires?

What is the ideal trans temp? Under 180F?

Maybe this is a good option?

 
It's all about high g forces with heavy throttle input. A lot of people run drag radials on the street. If you launch the car hard and you a pinned back in the seat hard the trans fluid is also thrown to the rear. Hard old style street tires won't do it so no problem there haha.
 

I just did a little heat shrink tube around the connector. I did bend a clip that was holding wires I think to help keep the filter situated and used the stock pan. I run a little over full. Sucking air hurts clutches and band.
 
It's all about high g forces with heavy throttle input. A lot of people run drag radials on the street. If you launch the car hard and you a pinned back in the seat hard the trans fluid is also thrown to the rear. Hard old style street tires won't do it so no problem there haha.

Yeah, and it might not even be that. These discussions have gone around in circles for years because everybody's speculating. I've been lucky enough to actually instrument my car. Here's my fastest autocross run from the 2019 Bristol National Tour event:

IMG_4628.JPG


Green line is transmission line pressure. Now, some of you experienced folks will see these pressures are low. This trans was hurt badly, it came out for an overhaul right after this event and the nylon stator support bushing had melted out of the pump. Oops.

BUT! It still worked, and this chart still can tell us if I uncovered the pickup:

The first arrow is pointing to the line pressure during a long sweeper. The car was pulling 1.2-1.5 G laterally for almost two seconds. Transmission line pressure dropped to ~25-30psi (left side arrow). But it settled at the same pressure after the run when I was at idle (right arrow).

So even during a long sweeper on super sticky tires pulling 1.2-1.5g, I didn't uncover the pickup and suck air. Same pressure as sitting level at idle in the pits.

This is a deep pan with a 700-R4 filter filled half a quart past full on the dipstick. So, go with a bottom feed filter for a street car. Anything more is just bling. If you want a fancy nice pan, that's up to you. But you don't need it.

If you're pulling 1.3 60' times and packing the front wheels past the lights, well, you're not exactly a mild street car on Radial TAs anymore, are you? Different discussion.
 
$100 for a 4L60 filter? Kind of ridiculous

It’s a kit consisting of a filter, a surface ground spacer (to space the pan down so you don’t smash the filter into the connector), two gaskets, longer bolts and a couple pieces of heat shrink to ensure the connector doesn’t get shorted.
The spacer is 1/8” or so and some may feel it’s necessary and some may not.

I thought this may be an option if you don’t need the cooling capabilities of the extra fluid.
 
What is the distance between the 2004R top feed vs the 700R4 bottom feed? Are we talking 1/2" or more?
 
This is a deep pan with a 700-R4 filter filled half a quart past full on the dipstick. So, go with a bottom feed filter for a street car. Anything more is just bling. If you want a fancy nice pan, that's up to you. But you don't need it.

If you're pulling 1.3 60' times and packing the front wheels past the lights, well, you're not exactly a mild street car on Radial TAs anymore, are you? Different discussion.

So a 700R4 filter, Hughes Deep pan, and about a 1/2 quart to 1 quart overfill will suffice for a low 12 second car. Sound right?
 
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