What Transmission do I have

**Air Force One** · 02-27-2009, 03:21 PM

1990 Chevy Cheyene 1500, 4 speed automactic..I've been told that this transmission is a 4L60E, BUT my Haynes auto manuals says "Beginning in 1991, an electronically controlled transmission, the HYDRA-Matic 4L80-E was installed in some vehicles" ??? Do do I have a 4L60 or 4L60-E? The 4L60-E are not equipped with a throttle Valve (TV) cable assembly. This 1990 chevy truck has a 305 Engine, and when it goes from first to second it has to rev up before it shifts into 2nd. It DOES get better when it warms up some. I put a new filter and oil in it already, and I also put a quart of LUCAS TRANS OIL in it as well...any advise of what I should be looking for or doing? Thanks for your look and advise...AF1

**k.daddy1** · 03-02-2009, 01:50 PM

You have the 4L60, the beefed up version of the 700R4. The 4L60E didn't get put into trucks until the end of 94 I believe.

**BBC4EVER** · 03-02-2009, 03:05 PM

I agree, I believe the 4L60. How many miles are on it? There is a shift silenoid for 1-2 and 3-4 on the back side of the valve body (in the pan). I'm not a trans expert, but have serviced quite a few of my own. I don't know how that trans is controlled (cable or vacuum). Make sure the fluid level is spot on. If it's off (especially too full) it will really mess up the shifting and the trans itself.

**OleBlue93** · 03-02-2009, 03:41 PM

i have a 93 silverado 2500 light duty with the six lug axles and mine has a 700r4. count the pan bolts the 4l60e is a newer version like they said above but its electronical it has the same pan as the 700r4

4l80e has 17 bolts
700r4 &4l60e has 16 bolts

**Air Force One** · 03-02-2009, 05:04 PM

This trans has 130,00 on it. What would you recommend that I check? Has oil changed + Filter..its shifts hard going from 1st to 2nd. thanks for your help

**Jimmiee** · 03-02-2009, 05:20 PM

The 4L60 is in fact the 700R4. Same same. The 4L60E is electronically controlled as is the 4L80E. The 4L60E was introduced in 1990.

Jim

**Jimmiee** · 03-02-2009, 05:39 PM

I sent that post off before I was finished. I wanted to say the 700 or 4L60 models are cable controlled and the E's are controlled by an EPC solenoid.
If your 4L60E starts shifting hard on the 1-2 chances are it has a P1870 code stored in memory. This is a common torque converter slip code. This code may or may not turn on the check engine light. Best way to tell is to scan the computer for codes. If there are no codes then another thing that can cause a harsh 1-2 shift is a broken accumulator spring. These springs are very easy to change once the pan is removed.

**Crawdaddy** · 03-02-2009, 06:33 PM

In a 1990 C/K with the 305, you SHOULD have the 4L60E. They introduced the 4L60E in either 89 or 90. However, if it has the 700R4 and the throttle valve cable in improperly adjusted, the transmission will shift weird and it WILL fail quickly. However, it sounds like you may have valve body issues assuming it's a 700R4. On my 700R4 I had a freshly rebuilt transmission from what I now know is a lousy rebuilder and there was a spring or something in the valve body that was not right. I replaced all the springs with a shift kit and that fixed the issue and gave me a slightly more agressive shift pattern.

**k.daddy1** · 03-03-2009, 09:21 AM

700R4 introduced in 1982
4L60 introduced in 1990
4L60E introduced in 1996
4L60E was originally introduced in 1995 with a 13 pin electrical connector, then in 1996 was changed to a 11 pin connector. That's why the 95 chevy vehicles with the 4L60E can only be changed out with a tranny from a 95. Check the books if you don't believe me.

**CJlambertz71** · 03-03-2009, 01:00 PM

ok i have a question about my transmission, i cant tell if its a getrag trans or a new processor trans
i have a 1991 k1500 z71
its a 5speed manual
and the number on it is GM8672286