2004R questions

[65skyturbo]

I have had several 2004R's in the past and I know about the codes on the tag to identify them. But what do you do if the tag is missing? There is just a spot of silicone next to the shift lever where it used to be. There is no evidence that there was ever a tag on the passenger side tailshaft area. Is there a way to identify what model it is by the stamped partial VIN above the pan rail? Mine is 1HP125848. Also does anybody have a copy of an older AC Delco or Goodwrench transmission catalog? It has been discontinued from GM so it is not in their current catalog. I believe this unit was a GM SRTA unit. It has the code ACHX spray painted on the upper case. It also has a tag on it that says RT54BA. I'm hoping to find out what this trans came out of, or at least what year it is. The time clock casting says 991 but I don't think that has anything to do with the year since these trans were no longer used after 1990. Unless they were still manufactured for replacement units. Anyways, hopefully somebody can help. Thanks.

[turbo nasty]

Pull the pan and see if the VB has any letters on it like BR3, CZ, etc.
Look for 2 Psi switches
Lets us know the code if found
ALso pull the governor and see what color the gear is on it

[65skyturbo]

Valve body has a yellow paint dot and code HC2 painted in white. Only one pressure switch screwed into the valve body but the wires run into some sort of round 2 conducter switch before going to the harness connector on the drivers side. Only two wires are used at that harness connector. Inside case has 401 casting number with purple paint on it. Governor has A6 on it, and torque converter has 6 stamped all the way around. Speedo gear is white with 13 teeth. I know it is not a GN trans, but I still wonder what it came out of and what year it is?

[jmd]

Originally Posted by 65skyturbo

Valve body has a yellow paint dot and code HC2 painted in white. Only one pressure switch screwed into the valve body but the wires run into some sort of round 2 conducter switch before going to the harness connector on the drivers side. Only two wires are used at that harness connector. Inside case has 401 casting number with purple paint on it. Governor has A6 on it, and torque converter has 6 stamped all the way around. Speedo gear is white with 13 teeth. I know it is not a GN trans, but I still wonder what it came out of and what year it is?

switch in the valvebody is the 4th gear pressure switch. The 2-wire item is the torque converter clutch solenoid [TCC]

[65skyturbo]

What I'm looking at is not the TCC solenoid or the 4th gear switch but another item. There are three things that are wired together. I'm guessing it is some sort of temperature switch that governs the TCC if it is too hot or cold. None of the previous 2004R's I've worked on have had it. It is a 2 prong switch, about 5/8 diameter and it is not screwed into the valve body. It is just held on by one of the valve body bolts. Anyways, I need to figure out what it is so I can decide if I want to keep it or get rid of it. I will be setting the transmission up so that it only locks up in 4th gear with no computer.

[SSedan64]

My ATSG Manual show for 1989 & 1990 Models CTF & CUF there's a Temp Switch mounted to a bolt on the rear of valvebody a little towards the drivers side. It can be bypassed. I believe it was used for uphill driving to route more of the fluid from the converter through the cooler. Some of the 700R4s had this also.

[65skyturbo]

I thought it was some sort of temp switch. Chances are, it will be deleted. Although I suppose I could leave it in as an added safety measure of keeping the trans fluid at lower temps. I wont ever tow with this car but I do live in AZ so I have the summer heat to deal with. Does the manual you refer to give the fluid temp the switch activates at? I can't remember if the fluid temp is hotter with the converter unlocked or locked? I think it is cooler when it is locked due to less slippage....?

[SSedan64]

It didn't give a activation temp. It only operates when the TCC is unlocked for extended periods as when driving in mountainous or very hilly conditions.. If the temp gets hot enough the switch will temporarily lock the converter and send fluid through the cooler to drop the temp. You could leave it or delete. I guess if you were gonna use a non-lockup converter it may be nessesary to delete it.

[turbofish38]

Originally Posted by 65skyturbo

Valve body has a yellow paint dot and code HC2 painted in white, torque converter has 6 stamped all the way around. Speedo gear is white with 13 teeth.

I show an HC code for 1986 B-Body with a 305 SBC.13 tooth drive gear was used on 2.41,2.56,2.73 rear axles.

[65skyturbo]

That is all very good information. When I was looking at the tranny, I noticed date codes from 1986 (governor housing), 1987 (servo), and 1989 (tranny case). Being that this is a GM SRTA transmission, I'm assuming GM just builds them using a large batch of parts. I wonder, however, if they are remanufactured so that one part number fits 95% of applications. Mine has code ACHX painted on the top of the case. I know they must have some specific applications because once I saw a GN with BR painted on the case.

[SSedan64]

The GM SRTA trans I've seen all had codes stenciled/painted on the top of case. Not sure what that code would be for. Any part will interchange between the 2004R trans. Here's a good link for decoding & a lot other HiPer Info.
THM 200-4R Information