Bracket Talk
Advice on our powerglide troubles
August 11, 2024, 10:32 PM
TD6297Advice on our powerglide troubles
Hi everyone, ran into a transmission problem in our dragster this weekend. Just wondering what I should be looking at on our powerglide. Time trials everything seemed ok, then first round, after backing up following the burnout sne had no first gear to stage then suddenly first was there and she staged the car although I think it was still not right as it seemed slow and difficult to roll into the beams. About 40 feet out, something released , and the engine zinged to the limiter, that let it shift into second gear and she drove slowly down the track.
When checking in the pits, when the transmission was cooled everything seemed ok. Reverse, first and second gears seemed solid. Ran the engine to the chip on the trans brake two times and it seemed fine. Left the transmission in first and loaded against the wheel brakes and first seemed ok. Shifted into second and it was also ok when doing this. Put the transmission into neutral and let off the foot brakes, and the wheels no longer were rotating. Raised RPM and still nothing. Spun the wheels by hand and they were free so nothing was locked up. Then on their own took off like nothing was wrong. I could repeat this every time.
The fluid is not burned, still a nice red and there is no sediment when pulling the dipstick out. I have not removed the transmission or pan yet to see if anything might be in the bottom, but it sounds like an oil problem not a hard part problem to me. A bad seal maybe? Just wondering what you guys think so I have an idea where to concentrate when tearing it apart. Thanks much for your input!
August 12, 2024, 04:32 AM
FootloosePossibly broke the planetarys and or sprag . This would be a good question for Trans Lady IMO Or FTI. I hope its not too bad. Its got to come out.
August 12, 2024, 07:48 AM
Yellow TicketI had a rooster comb throw me some odd stuff once, it wasn't broken, just enough to be bent and do some weird stuff.
August 12, 2024, 08:31 AM
TD6297quote:
Originally posted by Footloose:
Possibly broke the planetarys and or sprag . This would be a good question for Trans Lady IMO Or FTI. I hope its not too bad. Its got to come out.
My big concern is if it is a case problem as it only happens once the oil is hot. But havent seen this particular problem.
August 12, 2024, 08:32 AM
TD6297quote:
Originally posted by Yellow Ticket:
I had a rooster comb throw me some odd stuff once, it wasn't broken, just enough to be bent and do some weird stuff.
I had one that wasnt broken, but split so it would sometimes spread and caused weird grief also and was one thing I was going to look at once the pan is off.
August 12, 2024, 08:57 AM
Brandon@BTEI'd start by putting a pressure gauge on it if its not out of the car yet.
August 12, 2024, 10:07 AM
GoobTH-400

"Despite the high cost of living, it remains popular."
Dave Cook
N375
August 12, 2024, 11:03 AM
EmanPut a pressure gauge on it before pulling things apart.
August 12, 2024, 11:41 AM
Paul S/Qquote:
Originally posted by Eman:
Put a pressure gauge on it before pulling things apart.
ALWAYS.....
August 12, 2024, 12:05 PM
markemarkquote:
Originally posted by Goob:
TH-400
Think anyone here uses a 2 speed th400?
August 12, 2024, 12:14 PM
Brandon@BTEI wish more dragsters were engineered to accept a TH400.
August 12, 2024, 12:41 PM
markemarkSaw two PG failures in the isle I was pitted in this weekend. Never owned a PG and never will.
August 12, 2024, 01:39 PM
TD6297quote:
Originally posted by Brandon@BTE:
I'd start by putting a pressure gauge on it if its not out of the car yet.
yes, that is a good idea, it is still in. Just have to bring some gauges from work.
August 12, 2024, 02:09 PM
FTIx2 for putting a pressure gauge on it. make sure it can handle atleast 300lbs of pressure.
line pressure is usually right around 250 on a performance Powerglide.
FTI Performance
Competition Converters and Racing Transmissions
"Some call it cheating, we call it the competitive edge."
www.FTIPerformance.cominfo@ftiperformance.com
August 12, 2024, 03:49 PM
Goobquote:
Originally posted by Brandon@BTE:
I wish more dragsters were engineered to accept a TH400.
I know, right? Them things are 20 feet long, gotta be room for a real transmission in there somewhere, I've seen Lencos in there.
The availability of custom ratio gear sets has changed the game....finally.
I bought my 2.10/1.40 gear set from John Kilgore in 1999

Haven't had the pan off this unit since 2003
Your mileage may vary.

goob- sorry, went off topic, sorta.
"Despite the high cost of living, it remains popular."
Dave Cook
N375
August 12, 2024, 06:12 PM
BP758quote:
Originally posted by Brandon@BTE:
I wish more dragsters were engineered to accept a TH400.
LIKE!
California Screaming!
Raceless in California!
August 12, 2024, 07:56 PM
imakehpquote:
Originally posted by BP758:
quote:
Originally posted by Brandon@BTE:
I wish more dragsters were engineered to accept a TH400.
LIKE!
The trans just hangs on the rear motorplate doesn't it? Is a turbo so much wider it doesn't fit between the frame rails?
.
Dave
F J B
August 12, 2024, 08:34 PM
Brandon@BTEBellhousing dimension isn't the issue. But we are getting off topic here big time - post up some pressures and perhaps we can offer some guidance.
August 12, 2024, 09:53 PM
BP758quote:
Originally posted by imakehp:
quote:
Originally posted by BP758:
quote:
Originally posted by Brandon@BTE:
I wish more dragsters were engineered to accept a TH400.
LIKE!
The trans just hangs on the rear motorplate doesn't it? Is a turbo so much wider it doesn't fit between the frame rails?
What I found Dave
A Powerglide and a TH400 do not vary much in width, but length difference will range from 18 inches on a dragster-style Powerglide to 28 inches in a door car. A TH400 with a standard 4-inch extension housing measures 29.5 inches, although there are rare cases where a TH400 could be 34.5 or 38.5 inches.
Short shaft glide is 25+
Long shaft glide is 27+
Not meant to derail TD6297
California Screaming!
Raceless in California!
August 12, 2024, 10:37 PM
TD6297quote:
Originally posted by Brandon@BTE:
Bellhousing dimension isn't the issue. But we are getting off topic here big time - post up some pressures and perhaps we can offer some guidance.
I will get main and low pressures cold and hot as soon as I can.