Question: 4L60E interchange compatibility

[Low drag - High speed]

I have a '95 coupe with a whining 4L60E transmission. I have a good used 4L60E liberated from a 1997 Camaro Z-28 that threw a rod. My plan is to swap tailshafts on the two and stick the good one in the 'Vette.

Then I start hearing from some shade tree mechanics that there will be issues with solenoids and torque converters and computer prompts and shift points and on an on and on.


Who can enlighten me?

 

[John Robinson]

You might want to check out the gear ratios between the two transmissions. Just because they are both 4l60e units does not mean they are the same. The determining factor is do they both have the same part number. Each car line has the transmission built differently for each application. I know this because I worked 30 years for GM in the manual transmission plant here in Muncie. My last few years was as a project manager for the prototype build and procurement of prototype parts. Even though we supplied transmissions to Chevy and Oldsmobile and GMC and Pontiac etc each division ran it's own testing and internal parts often were different for each product line. You might look at two transmission's and there parts from say a Corvette and a Camaro or Firebird and they would look the same but they are not. That is why each Div of GM had different part numbers that were exclusive to there product line. I do believe that the Corvette transmission had an extra pressure valve to make the 1st to 2nd shift more positive. It is my understanding that only the Corvette was fitted with this extra shift valve.

 

[Low drag - High speed]

Would it function, then?

Even without the xtra valve, would the Camaro transmission still function normally? The car is just for street and touring, not competition.

 

[John Robinson]

Even without the xtra valve, would the Camaro transmission still function normally? The car is just for street and touring, not competition.

I do not know. It is to help the shift into second gear only. It could be that because of the weight and the gearing of the Corvette that it needs to have an extra boost of pressure to firmly engage the gear. But you can bet if GM thought it necessary to spend the extra money to do it then they were eliminating a problem. After all they spend multi millions of dollars testing each component before they put it into production. Those differences do not happen by accident they are there to solve a problem.

 

[Low drag - High speed]

Point well taken.

I guess I'll compare the numbers first, then pull the tranny out and compare parts and placement on the insides of both. Perhaps the pump and clutch packs on the good one will fit into the whiny one in the car. If I had the bucks, I'd just do a rebuild on the Corvette trans with all new soft and hard parts ... and maybe a mild shift kit in the valve body.

But a retired disabled veteran has to make do with what's on hand.

 

[John Robinson]

I fully understand disabled and fixed income. I went out at 51 in 1991. My Corvette isn't real pretty under the hood and if you look there are a lot of home made pieces to keep the car running. But if I get on it it goes like H===. And I still take it out for 600 to 700 mile day trips. Do what you have to keep it going. Let us know what you find out when you compare the two units. And if you have any valve body parts left for sale let me know. I have been nursing my transmission for over two years with a bad valve body or downshift solenoid. Oops mine is a 4l60 not a 4l60E big difference between them. Good luck on what you decide to do.

 

[Low drag - High speed]

Thanks again.

I will have a slight delay before I begin. My stepson wants to take it to prom, whining trans or not. Hope he doesn't increase the work load any with extra broken parts.

I'll drop a thread once I'm there.

 

[John Robinson]

Just out of curiosity have you checked the fluid level in the transmission. Another thought I normally don't recommend snake oil cures but you could try one of the trans. additive products to see if the noise goes away. What have you got to loose.

 

[Hib Halverson]

When you say "whining transmission" can you be more specific?

Whines in all gears?
Whines in some gears or one gears? If so which ones.
Whines all the time in gear or not?

How many miles on the transmission?
Has it received periodic service, such as filter changes and fluid changes?

When you pulled the trans pan off, what did you find in the bottom of it?
More than a nickel's worth of medal powder?
Any larger chips or chunks of metal?