I have always put my PG in neutral at the stripe. I was discussing this with someone the other day and they asked if that over speeds the planetary. I don't know, anyone know for sure.

I always did with the TD and continued with the PST. Sonnex extreme planetary and never ever had any issues. Planet that's in the truck was in the TD

I do not see how anything would be spinning any faster than it was if in gear. I mean engine not going faster and rear end not going faster, Both are slowing just not one pulling on the other.

Nah, you're good with a pro brake. I think that comes from people trying to neutral a non clean T400.

I know the planetary will overspeed with a turbo 400. But I don't think so on a PG.

This message has been edited. Last edited by: sr4440, April 02, 2025 02:36 PM

Done it with a standard brake for over 20 years and never once EVER had an issue. I have even hit the kill switch while my foot was sstill wide open and in high gear, many times in a row, and have NEVER not once had an issue or seen an issue in the trans. Only people that have had issues with powerglides, are people that do not have a good shifter or a the cable is not adjusted properly and they manage to find reverse with the engine running.

quote:

Originally posted by 329L:
Done it with a standard brake for over 20 years and never once EVER had an issue. I have even hit the kill switch while my foot was sstill wide open and in high gear, many times in a row, and have NEVER not once had an issue or seen an issue in the trans. Only people that have had issues with powerglides, are people that do not have a good shifter or a the cable is not adjusted properly and they manage to find reverse with the engine running.

Yup, reverse is what I was thinking about on the pro brake comment.

quote:

Originally posted by CURTIS REED:
Nah, you're good with a pro brake. I think that comes from people trying to neutral a non clean T400.

I did that about 3500 times, standard brake, then someone finally spooked me.
Probably not an issue running 126 mph 1/4 mile?
Now I kick it into 2nd, since there's no engine braking, probably no better than kicking it to Neutral.

quote:

Originally posted by Goob:

quote:

Originally posted by CURTIS REED:
Nah, you're good with a pro brake. I think that comes from people trying to neutral a non clean T400.

I did that about 3500 times, standard brake, then someone finally spooked me.
Probably not an issue running 126 mph 1/4 mile?
Now I kick it into 2nd, since there's no engine braking, probably no better than kicking it to Neutral.

I've never had a T400 just heard about it. I've only ever ran a Glide and I've always had a pro brake.

Sounds like people getting NON clean neutral TH400s confused with Powerglides...

you will be fine to continue putting it in neutral after the run.

-Dalton

quote:

Originally posted by sr4440:
I know the planetary will overspeed with a turbo 400. But I don't think so on a PG.

On a TH400 it doesn't overspeed the planetary, it overspeeds the direct drum, 3.5 times driveshaft speed if memory serves me correct. That's what causes it to explode. It goes from driveshaft speed to that INSTANTLY......on the clean neutral versions, it keeps the direct drumm applied but releases the forward drum to allow neutral, and keep the direct drum at driveshaft speed....kicker is, you have to keep the engine running because you need the pump to keep working....I think that's how they are done anyway......

keep the engine running, even with a PG. Keeps the pump turning and lube circuit lubed (and cooled). I had a problem with that when I went to EFI, had to work with the efi settings to hold the rpm up a little bit. Have since went back to mfi. easier to deal with, imo, on a bracket car.

quote:

Originally posted by M802138: I had a problem with that when I went to EFI, had to work with the efi settings to hold the rpm up a little bit. Have since went back to mfi. easier to deal with, imo, on a bracket car.

Were you using gas or methanol with EFI?

I don't recommend it, nor does Sonnax (it's in their technical documents). Cutting the engine is worse than going to neutral, but engine builders don't warranty anything and most companies in our industry warranty gear sets for 2 years so there you go.

The powerglide does accelerate the small sun gear rapidly when neutral is selected which spins the direct drum as the input shaft slows down at a variable ratio. Drums can and do explode, planetary pinion speed is beyond the rating of the needle bearing design but many people get away with it and many don't.


Hutch