I just got back from a 7 auto parts store tour. I am trying to purchase a lower speedometer cable for my 88 IROC, which happens to have a mechanical speedometer (might be important).

Most every store had a cable that their computer said fit. They all had the same cable. It doesn't fit.

Here is a picture of my cable.

The left side connector in the picture mates to the upper cable, which continues to the speedo head.
THe right side connector pictured threads into the tranny.

Huh?

 

Sothing about that doesent look right. All the speedo connections are male and should look like the picture on the right, even the one at the speedometer its self.

 

I know - I am confused.

 

That connection shown in your picture is right under the brake booster right? my 87 iroc has that same connection, like a 2 piece cable..lower cable comes from the trans. and connects to the upper cable...I dont know any part #'s as I've never had to replace it. I believe the connecter on the right is the one that come out of the firewall and sits under the brake master cylinder and the connecter on the left screws into that and continues on to the tranny, thats what mine does...hope this helps

-Brian

 

Blueiroc -

Yes, we do have the same setup. The routing is exactly as you describe. I was beginning to worry that this was some jury-rig setup that a previous owner put in. I'm glad to see that someone else has this.

Now I guess I have to wait until the Chevy parts desk opens on Monday.

 

Correction - the way I describe the connections is the way that I said. Your description on where the differents ends go is backwards. However the routing you state is correct.

Anyone know that Delco part number for this cable?

 

Why not just buy the one piece cable and be done with it? Or do you have cruise? I parted out a 87 firebird with a 2.8 and it had a one piece speedo cable in it.

 

Maybe I sould get one cable and be done with it... Off to the garage to pull the instrument cluster.

WHY DOES EVEYTHING HAVE TO BE SO HARD?!

 

How is the one piece cable routed? I want to convert to one piece since my cruise control doesn't work, I never use it in cars that have it, and I want to clean up my engine bay.

 

I can't imagine it making much of a difference how it is routed as long as there are no sharp bends in it....

 

I've seen those before. I honestly think they are leftovers from the old cruise control setups, which used the cable for the cruise. Why it would have been on an 88 is anybody's guess.

The one piece deal should work fine in place of the two piece unit. Take your old one out and match it up to what they have, the only important things are length and the end type, and I am guessing the end type is going to be the same no matter what.

 

Well, I decided to at least wait until Monday to see if I can get an exact replacement lower cable. If not, I'm going the single cable route...

I'll report back what I learn. I know a guy who is a parts manager for a local Checvy dealer and if anyone can get me one, it will be him.

Stay tuned.

 

My local Chevy parts manager cleared this mystery up. Some Camaros left the factory with the "standard" two-part speedometer cables, even though the cables didn't go through the cruise control unit. The actual replacement recommended by Chevrolet is to replace both the upper and lower cable with a single cable.

Chevy Part Number 25033662

 

Good info. I'm supprised though, when I took the cruise controll off of my Camaro I couldent find a single replacement cable and had to nab one out of a 72. Good to know they finally make them, at least thier saying it will work for our applications anyway

SSC

 

This gets more interesting...

I got the cable yesterday from the only Chevy parts department with one in stock ($50!) The cable looks like the old one - it has that weird break between the upper and lower cable just lke the one in the car. So, I decided to decouple the upper and lower cables to verify that it was the same. Since I know that spinning the upper cable turns the speedometer, I figured I could avoid tearing the interument cluster out again.

When I tried to separate the two cables, they seemed fused together. Now I am wondering if this isn't by design and if separating them will cause me grief.

Also, it appears that both cable segments are shorter (I still have the old one in pieces and need to confirm this). If this is true, the lower cable may be too short to replace on it's own. I still may have to replace the whole cable.

I'll update you all.

 

I had the same situation with my 87 SC. I needed the lower cable due to it braking at the transmission. All the parts stores I went to only had the one piece cable. I didnt want to take my dash apart to pull the upper cable. Instead I went to the junkyard ,and got the lower half of the cable. It fit perfect ,and problem was solved. It may take some searching ,but you can probable find one in your local junkyard. Also the two halfs are indeed hard to unscrew. I sprayed mine with WD40 ,and let it sit. Next day came apart no problem.Hope this helps.

 

Well, I got some time to look at this last night (after I pulled the alternator out of my Monte Carlo SS...)

Here's the deal:
The above part number is the EXACT replacement for the original cable. The lengths are indeed the same. Using a 1" open ended wrench and a pair of vice grips, I was able to break the cable segments apart and everything appears OK.

After I get my MC SS alternator tested and installed, I will finish this job.

The above part number is indeed correct and an exact replacement.

 

Good news: New alternator works OK in the Monte Carlo SS.

Good news: I replaced the lower speedo cable in the IROC and the speedometer now works fine.

Bad news: Because it was so tight to connect the cable on the upper end (under the master cylinder), I broke a brake line (or something) an I have a fluid leak. I was too pissed to look at it yesterday. Today is another day.

In summary - yes, the above part number is correct. Yes, it is an exact replacement. Yes, it is a real PITA to replace just one part of the cable should you find that you have this configuration.

Good luck, all.

 

hey guys this is my first post. i'm dealing with this issue on my 1988 camaro. how difficult is it to replace the two piece cable with a one piece? are there any major mechanical differences? i simply can't get that coupler to give, even after hitting it repeatedly two days in a row with p blaster. i noticed a rubber stopper or something of the likes at the firewall, so i don't know how one is supposed to pull the cable through without damage to that rubber stopper.

 

just to let you know nicely, this post is 6 years old, people like to jump on you for bringing post back from the dead

that rubber stopper is probally a gromet and it should pop out then pull the cable through