Turbo 400 Question

sox · 02-13-2016, 09:14 AM

Im putting together a Street Car and it has a 400 Turbo Trans in it.It takes about 20 seconds to go in gear.Once engaged it shifts fine.I pulled the pan off last night and the filter was slapping around.After some research,they say its suppose to be that way.I also seen where a guy put a spring on the shaft where it mounts to tighten it up from slapping around.Any suggestions about this and could that cause the trans not to engage right away.

Alan Roehrich · 02-13-2016, 10:52 AM

Usual causes:

Low fluid
Clogged filter
Air leak at either end of the filter tube
Excessive converter drain back
Hard lip seals

A spring to hold the filter down against the head of the filter bolt won't hurt, but it is not necessary.

sox · 02-13-2016, 12:38 PM

It does leak thru the seal.I did talk to a guy who suggested seal conditioner from GM.

Alan Roehrich · 02-13-2016, 12:48 PM

Seal conditioner is useless. It just swells the seals temporarily. You can do that with a pint of DOT 3 brake fluid. It will probably do nothing at all. It may just hasten the need for an overhaul.

The lip seals I referred to are inside.

Warm the car up to operating temperature, get it to move, then put it in park on a level surface and check the fluid level, make sure that the fluid level is right on the "full hot" mark. Then let the car sit for a day or two. Check the fluid before you start it. Then start the car and immediately check the fluid level. Note the differences.

Jim Kaekel · 02-15-2016, 11:34 AM

Quote:

Originally Posted by Alan Roehrich

Seal conditioner is useless. It just swells the seals temporarily. You can do that with a pint of DOT 3 brake fluid. It will probably do nothing at all. It may just hasten the need for an overhaul.
The lip seals I referred to are inside.
Warm the car up to operating temperature, get it to move, then put it in park on a level surface and check the fluid level, make sure that the fluid level is right on the "full hot" mark. Then let the car sit for a day or two. Check the fluid before you start it. Then start the car and immediately check the fluid level. Note the differences.

Alan is correct, lip seals are probaly old and hardened up, causing a ton of oil pressure leakage. Time for a rebuild. I presume you did change the oil filter when you removed the pan as the stock style filter is easily clogged? If it's clogged, you'll hear a "screaming" noise when you start the engine caused by the pump and converter starving for fluid.

sox · 02-16-2016, 08:58 AM

Replaced the Filter and New Fluid and still is lagging going into gear.Looks like a Rebuild is in order.Thanks Guys for the info..

ss3011 · 02-16-2016, 10:11 AM

Make sure your linkage is adjusted correctly, it needs to be on the drive stop, when the shifter is in drive .

Lou Jeffery · 02-16-2016, 06:04 PM

A very common issue with a Turbo 400 or any other automatic with a gear pump is worn gears and crescent. Do not overlook the condition of the pump when doing a freshen up. The pump is designed for the life of the vehicle but when line pressure is increased from a shift kit, manual valve body or trans brake there is much more strain and hydraulic side loading causing wear. The worst case scenario is a street driven vehicle.

02-13-2016, 09:14 AM	#1
sox Junior Member Join Date: May 2008 Posts: 99 Likes: 21 Liked 13 Times in 8 Posts	Turbo 400 Question Im putting together a Street Car and it has a 400 Turbo Trans in it.It takes about 20 seconds to go in gear.Once engaged it shifts fine.I pulled the pan off last night and the filter was slapping around.After some research,they say its suppose to be that way.I also seen where a guy put a spring on the shaft where it mounts to tighten it up from slapping around.Any suggestions about this and could that cause the trans not to engage right away.

02-13-2016, 10:52 AM	#2
Alan Roehrich Veteran Member Join Date: May 2006 Location: Murfreesboro TN Posts: 5,105 Likes: 1,561 Liked 1,788 Times in 408 Posts	Re: Turbo 400 Question Usual causes: Low fluid Clogged filter Air leak at either end of the filter tube Excessive converter drain back Hard lip seals A spring to hold the filter down against the head of the filter bolt won't hurt, but it is not necessary. __________________ Alan Roehrich 212A G/S

02-13-2016, 12:38 PM	#3
sox Junior Member Join Date: May 2008 Posts: 99 Likes: 21 Liked 13 Times in 8 Posts	Re: Turbo 400 Question It does leak thru the seal.I did talk to a guy who suggested seal conditioner from GM.

02-13-2016, 12:48 PM	#4
Alan Roehrich Veteran Member Join Date: May 2006 Location: Murfreesboro TN Posts: 5,105 Likes: 1,561 Liked 1,788 Times in 408 Posts	Re: Turbo 400 Question Seal conditioner is useless. It just swells the seals temporarily. You can do that with a pint of DOT 3 brake fluid. It will probably do nothing at all. It may just hasten the need for an overhaul. The lip seals I referred to are inside. Warm the car up to operating temperature, get it to move, then put it in park on a level surface and check the fluid level, make sure that the fluid level is right on the "full hot" mark. Then let the car sit for a day or two. Check the fluid before you start it. Then start the car and immediately check the fluid level. Note the differences. __________________ Alan Roehrich 212A G/S

02-16-2016, 08:58 AM	#6
sox Junior Member Join Date: May 2008 Posts: 99 Likes: 21 Liked 13 Times in 8 Posts	Re: Turbo 400 Question Replaced the Filter and New Fluid and still is lagging going into gear.Looks like a Rebuild is in order.Thanks Guys for the info..

02-16-2016, 10:11 AM	#7
ss3011 Senior Member Join Date: Feb 2002 Location: Southeast Michigan Posts: 909 Likes: 70 Liked 239 Times in 114 Posts	Re: Turbo 400 Question Make sure your linkage is adjusted correctly, it needs to be on the drive stop, when the shifter is in drive .

02-16-2016, 06:04 PM	#8
Lou Jeffery Junior Member Join Date: Nov 2013 Posts: 91 Likes: 0 Liked 0 Times in 0 Posts	Re: Turbo 400 Question A very common issue with a Turbo 400 or any other automatic with a gear pump is worn gears and crescent. Do not overlook the condition of the pump when doing a freshen up. The pump is designed for the life of the vehicle but when line pressure is increased from a shift kit, manual valve body or trans brake there is much more strain and hydraulic side loading causing wear. The worst case scenario is a street driven vehicle.