Transmission advice please

[wymjym]

My 97 sho gave up its tranny at 88K.
I had a local shop rebuild it and the car was returned the other day.
The first thing that I noticed was that it felt as if it had a ‘low’ stall converter in it. It just didn’t have the get up and go, at slower speeds it actually turns less rpms than it used to…but that isn’t the big issue. It shifts very erratically. Most times if I give it small throttle inputs when it thinks it should shift…it generally will upshift rather than hold the gear or down shift. If I give it ½ or greater throttle everything seems fine.
I don’t think there is a break in period for automatics (unless there were metal parts that ride on each other replaced).
Since going back to the shop will be a big time killer I want to be certain that there isn’t something that I might be able to handle myself.
Advice would be appreciated.
Maybe a bottle of Lucas would help?
wj

 

[Silvapain]

Do NOT put any snake oil in a freshly rebuilt transmission...or any transmission for that matter.

The V8 SHO torque converter is unique - the SLO and V6 SHOs have different TC's. It's common for a non-V8 torque conveter to be installed.

You can tell a V8 TC because it will have 4 "ears" in the snout. The V6 SHO has 3, and the SLO has only 2.

 

[wymjym]

well since the tranny is in the car and 'urging' the shop to pull it apart will take a bit of convincing on my part, I ask the question, is the condition I am describing attributed to an incorrect torque converter or ?????
I do know that they had to special order the converter as the local suppliers did not have one (that doesn't mean it is the correct one but suggests that it should be)
wj

 

[venom]

well since the tranny is in the car and 'urging' the shop to pull it apart will take a bit of convincing on my part, I ask the question, is the condition I am describing attributed to an incorrect torque converter or ?????
I do know that they had to special order the converter as the local suppliers did not have one (that doesn't mean it is the correct one but suggests that it should be)
wj

Hold the brake and roll into the throttle , where does the tach go to? if it isn't above 2500 RPM it isn't a SHO converter.

 

[ThatShoGuy]

Hold the brake and roll into the throttle , where does the tach go to? if it isn't above 2500 RPM it isn't a SHO converter.

what do you mean by "roll into the throttle" ive never heard that used?

 

[wymjym]

Hold the brake and roll into the throttle , where does the tach go to? if it isn't above 2500 RPM it isn't a SHO converter.

I'll check that out later on today!! thanx....
as to the weird shifting? would that also be related to an incorrect torque converter?
wj

 

[SHOZ123]

The stall speed depends on the condition (efficiency) of the drive train too. If the engine is down on power it will not stall as high as it normally would. Brake stall speed on a SHO is anywhere from 2300-2800 rpm. The Ford manual says 2800-3200 but I have never seen that on any of the numerous TCs I've had. You should have to really stand on the brakes to keep the car from moving when doing the brake stall test.

The OEM TCs have the 4 ears. I have one build for the V8 and is considered a high stall. It has no ears and stalls out at 2600 rpm.

If it has two ears it is only a single clutch TC. 4 ears and 0 ears are dual clutch.

 

[venom]

The stall speed depends on the condition (efficiency) of the drive train too. If the engine is down on power it will not stall as high as it normally would. Brake stall speed on a SHO is anywhere from 2300-2800 rpm. The Ford manual says 2800-3200 but I have never seen that on any of the numerous TCs I've had. You should have to really stand on the brakes to keep the car from moving when doing the brake stall test.

The OEM TCs have the 4 ears. I have one build for the V8 and is considered a high stall. It has no ears and stalls out at 2600 rpm.

If it has two ears it is only a single clutch TC. 4 ears and 0 ears are dual clutch.

Both of my V8 ATX's exhibited stall speeds of 2800 - 2900. One of those was always a slow car at the drag strip when compared to other cars.

 

[SHOZ123]

I should also add the disclaimer it is not unusual for the tach to be off by ~200 rpm either.

 

[venom]

I should also add the disclaimer it is not unusual for the tach to be off by ~200 rpm either.

Valid point.

 

[wymjym]

almost but still no cigar!

I thought I would check the connections before calling the shop.
So, I pulled the connection off of the range selector switch and saw that the silicone rubber seal was basically covering two of the contact areas...looked closer and the pins had not poked through..so those connections were isolated! Refit the seal, sprayed with contact cleaner, yadayadyadya.
Drove it up the road....much, much improved shifting. Much improved off line as well. Tried to power brake and saw around 2700rpms...so far so good.
the not so good reared its head when I went for an extended drive. Originally I would describe the sho tranny shifting characteristics as rubberband like in very light throttle applications. My tranny now jumps up and down 300 rpms in those situations with a decernable surge (almost as if there is an instant lockup/lockout.
So...is it the valving, the rebuild or could it still be a torque converter that might not have the 2 plate modulating clutch? I assume that since it does shift fine at anything but low throttle situations that it must have a modulating clutch rather than an on/off.
Still in need of advice.
wj

The stall speed depends on the condition (efficiency) of the drive train too. If the engine is down on power it will not stall as high as it normally would. Brake stall speed on a SHO is anywhere from 2300-2800 rpm. The Ford manual says 2800-3200 but I have never seen that on any of the numerous TCs I've had. You should have to really stand on the brakes to keep the car from moving when doing the brake stall test.

The OEM TCs have the 4 ears. I have one build for the V8 and is considered a high stall. It has no ears and stalls out at 2600 rpm.

If it has two ears it is only a single clutch TC. 4 ears and 0 ears are dual clutch.