Plan B, rebuild/reseal the SP400

[CTX-SLPR]

Ok, I've finally come to the conclusion that the 4L80E swap isn't going to happen as I've made 0 progress on the Riviera since like December and still have like 5 things to do the DD's that eat up all my garage time. Since I've got a driveshaft, mount and speedo gear correct for the 400 I'm just going to have to redo it. I don't have the time to do it myself and I don't even know what's wrong with it other than fluid comes out at an alarming rate when it's sitting and I have no idea if it's dripping while driving.

How much can you expect to pay for a refresh on a trans at a professional shop and how much if worst case the softparts are toast?
I got quoted $600-800 by Western Trans for a carry-in full softparts rebuild (no idea of that includes converter)
The local performancish transmission shop quoted me $700-900 but that was with converting it over to the later style filter and replacing the early "shoe heal" pan with a later model flat pan. I also think they said that would be converting it to a fixed stall and giving me the switch pitch stuff to sell.

I honestly want to keep the switch pitch and get it rebuilt, I don't really care about the converter being rebuilt. Like I said, I don't have the time and money isn't exactly abundant either.

Thoughts?

[Gary 351C]

I'm a firm believer in picking one's battles, I'd have the tranny shop do the SP400 and get on with the rest of the car. The C6 in the Montego needs going through and since I haven't had a trans apart in 30+ years I'm going to have a local shop do it and have a warranty to boot. It's hard to pay someone else your hard earned dollars to do something you could probably do yourself, but never getting around to it is the biggest killer of motivation. My 2 cents.

[SuperBuickGuy]

the prices quoted seem about average. My experience is always buy from a shop with a glass window you can throw the transmission through if it doesn't work.... which might inform on why I don't have windows on my shop

[STINEY]

For TH400 switch-pitch stuff, Jim at TriShieldPerformance.com is the dude.

Here's a link http://trishieldperformance.com/

[squirrel]

Usually when it leaks when sitting, it's because the converter is draining back into the rest of the trans, and there is a seal leaking that is normally above the level of the fluid. Likely suspects are the dipstick tube, speedo seal, kickdown connector, and shifter shaft.

None of these require removing the transmission to fix.

[Huskinhano]

Usually when it leaks when sitting, it's because the converter is draining back into the rest of the trans, and there is a seal leaking that is normally above the level of the fluid. Likely suspects are the dipstick tube, speedo seal, kickdown connector, and shifter shaft.

None of these require removing the transmission to fix.

Interesting, I never thought about that and always wondered why I'd get a puddle and a big one at that when cars have sat for a long period of time.

[CTX-SLPR]

Well it's worth $15 worth of gaskets, O-rings, and bushings to try fixing every exterior leak point. How hard is it to replace the tail housing bushing? I have to replace the gasket because I can at least see it seaping so might as well while I've got it off.

If that don't work, time to get the trans shop involved because I'm sure if it's still leaking or slipping baddly it needs a full rebuild.

Thanks guys,

[squirrel]

The pump O ring can also leak...and I forgot the governor cover...

The bushing in the tailhousing requires a bushing drive to replace it. you can probably take the housing to a trans shop and have them do it while you wait, if they feel like it.

I can understand a shop not wanting to mess with the SP converter, it's hard to find parts.

[CTX-SLPR]

Anyone have the little tool used to get the shift shaft seal out? Looks like it's been discontinued at NAPA (at least they don't list it online) and eBay ones are pricey! Besides, I just need it for a week or so.

Thanks,

[CTX-SLPR]

Ok, replaced the modulator O-ring, governor cover gaskets, extension housing gasket (sprayed some copper on it before assembling it), and found I had no O-rings on the electrical pass through. I'll grab some O-rings this week to put on there (if you know the exact size I'd appreciate a heads up) to solve that issue.
I'm going to try the local parts houses to see if they have the shaft seal tool for rent or sale cheap. Worst case if I can't find one, can I double the seals up or will that do nothing to seal up the shaft?

Thanks,

[Beagle]

picture of the shaft seal? I'm having a tough time picturing it in my mind. The one we used to use on mower crankshafts was a tube with tapered threads that you tightened up into the seal and then ran a bolt down the middle of it to put pressure on the shaft, pulling the seal out.

It sat, unused, for the entire time I worked there. Small strong (baby craftsman square shaft) screwdriver under lip of the seal, between the seal and the shaft. Lean on it sideways a little (leverage point on something) Boink, out they come. The self propel PTO shafts on push size mowers was about the same size as a shift selector shaft, same story. They come out pretty easily. If you have to pull the shaft out for anything, they come out very easily with the shaft out.