NV3550 fluid change (is it full?)

thunderdriver007

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I couldn't find anyone specifically talking about this, although I've read many threads on the forum and they've been hugely useful - so thanks to everyone here.

I changed the transmission fluid in my TJ today ('03 with manual NV3550). I used the Redline MTL 75W80 as suggested here. Using a fluid pump with just over a 0.2 qt capacity, I transferred fluid from the bottle ~10 times until it started overflowing from the transmission. I roughly verified the 2.1 qts by the 1 gallon bottle being a little less than half full. Once it stopped running down the side, I poked my finger in the fill port but couldn't feel any oil below it. I transferred a little extra fluid and it immediately started running down the side of the transmission again. The jeep was parked on a flat surface.

My question is this - Is there some sort of cavity created around the fill port so the fluid doesn't pool there? I don't have an endoscope and couldn't really get a good look with my phone camera. I'm sure I'm overthinking this, but I want to make sure it's topped off. Thanks for the help.
 
If you made sure the fill tube from the pump was inserted at least 1", consider it filled.
When I did mine years ago, I parked the left side tires on a couple pieces of 2x4's, just to be sure of proper level when on flat ground.
 
I couldn't find anyone specifically talking about this, although I've read many threads on the forum and they've been hugely useful - so thanks to everyone here.

I changed the transmission fluid in my TJ today ('03 with manual NV3550). I used the Redline MTL 75W80 as suggested here. Using a fluid pump with just over a 0.2 qt capacity, I transferred fluid from the bottle ~10 times until it started overflowing from the transmission. I roughly verified the 2.1 qts by the 1 gallon bottle being a little less than half full. Once it stopped running down the side, I poked my finger in the fill port but couldn't feel any oil below it. I transferred a little extra fluid and it immediately started running down the side of the transmission again. The jeep was parked on a flat surface.

My question is this - Is there some sort of cavity created around the fill port so the fluid doesn't pool there? I don't have an endoscope and couldn't really get a good look with my phone camera. I'm sure I'm overthinking this, but I want to make sure it's topped off. Thanks for the help.

If there isn't a big puddle of gear oil all over your driveway and it all went in the gearbox, you're okay. If you notice gears start to "buzz" or grind, recheck it. If you're sure you're on a flat surface (which to the point it would matter if not, you would know by looking at it), run it.

Also: Props for using redline. I put Pennzoil MTF in my trans (NV1500) right after I bought it. Shifts like coins in a burlap sack now. Let me know how your shifts feel after you get it buttoned up, once the rain clears i'm putting redline in it.
 
Appreciate the responses guys. I'm convinced it's full now haha

@alittleoff - Thanks for the suggestion, I rolled my driver side tires up on a 2x4 and pushed a little more fluid in, I'd rather have a little extra than not quite enough.

@cooper32 - I drove it to work and back this week, about 10 minutes each way. I wasn't having any problems shifting before but it's got 117k and who knows if it's ever been changed before (bought with 113k). It's shifting nice and smooth, a little better than before. Unknown previous fluid brand and drained some brass shavings with the old stuff so I'm sure that helped too.
 
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Appreciate the responses guys. I'm convinced it's full now haha

@alittleoff - Thanks for the suggestion, I rolled my driver side tires up on a 2x4 and pushed a little more fluid in, I'd rather have a little extra than not quite enough.

@cooper32 - I drove it to work and back this week, about 10 minutes each way. I wasn't having any problems shifting before but it's got 117k and who knows if it's ever been changed before (bought with 113k). It's shifting nice and smooth, a little better than before. Unknown previous fluid brand and drained some brass shavings with the old stuff so I'm sure that helped too.

You should be good then. Just don't OVERfill it too much or else the fluid will aerate, and bearings wont get lubricated well at all.
 
@Jerry Bransford, I've gained a lot of TJ knowledge from reading your posts and replies, glad to hear from you. Any ideas on my original question? If it's overflowing from the fill hole, why can't I feel any fluid when reaching in? It's definitely full and definitely overflowing.. just expected to reach in and feel the fluid filling up to the bottom of the fill hole.
 
Probably because its temperature is room temperature or at least close to finger temperature. If adding more gear lube causes it to overflow and you have already added its usual two quarts to it it's full.
 
Besides the 2 methods to check the level discussed here, a 3rd option is to use a telescopic inspection mirror and flashlight to see into the fill hole.
 
This forum is awesome. Been lurking around just reading all the wisdom and advice. Wanted to change the transmission fluid. Bought the Redline MTL, since it is universally praised, and it made a huge difference in the shifting. Slowly working through all the fluids, since I don't know the history, up next are differentials and the transfer case.