Transmission goes boom.

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

Supercharged111

Truly Awesome
Joined
Aug 20, 2015
Messages
12,615
Reaction score
15,240
I agree. Any time I have been towing and I can keep it in 3rd with the TC locked everything is good. When I have to use 2nd though things start to heat up quick since the TC doesn't lock in 2nd. Have any of you ever had the TC re-programmed to lock in 2nd??

The 4L80 is programmed to lock 2nd WOT from the factory. I disabled that as it was sapping my pulling power in 2nd. That was before the cam, rockers, intake, and blower though. I've never been stuck in 2nd long enough to get the trans past 210.
 

L31MaxExpress

I'm Awesome
Joined
Apr 21, 2018
Messages
5,890
Reaction score
7,539
Location
DFW, TX
I agree. Any time I have been towing and I can keep it in 3rd with the TC locked everything is good. When I have to use 2nd though things start to heat up quick since the TC doesn't lock in 2nd. Have any of you ever had the TC re-programmed to lock in 2nd??
ALL of mine locked in 2nd. My 83 G20s 700r4, the 92 4L60 I replaced it with when it had the TBI 350 and my 97 Express van 4L60E.
 

L31MaxExpress

I'm Awesome
Joined
Apr 21, 2018
Messages
5,890
Reaction score
7,539
Location
DFW, TX
Always run a cooler and a temp gauge. Heat is the number one killer of transmissions. How does a 60e die behind the 2.2 in the s10? It has nothing to do with power and everything to do with lack of power. Torque converter locking and unlocking more often, more gear hunting. All of that generates heat. Heat kills. In my 98 k1500 I don't let mine get over 200*f. 576000km(357000 miles) and it's the original transmission. I have towed as much as 8000 pounds. I tow in 3rd. I don't let it gear hunt, I keep the TC locked as much as possible. I watch the tranny temp. It's surprising how fast the temp climbs with just a bit of spirited driving when it's a hot summer day. Won't take long to start reducing the life of the transmission. I also change fluid regularly. Keep it cool, keep fresh high quality fluid in it and it will last. Make sure you have a good builder too. Sometimes they miss one little thing and that's the difference between the transmission lasting and not. They replace the 3-4 clutches with HD clutches cause they burnt up. But they don't figure out why they burnt up and then overlook that the seal on the forward piston is bleeding pressure which essentially causes the same thing as riding the clutch in a manual. You could put the best 3-4 clutch in that transmission in the world but if that piston is bleeding pressure the clutches will fail prematurely. Make sure you have a good builder that doesn't just know transmissions, make sure he knows 4l60e's.
My failures were not heat related. They were hard parts failures. I did not even put a hitch on the 97 Express until after I had 4L85E swapped.
 

Supercharged111

Truly Awesome
Joined
Aug 20, 2015
Messages
12,615
Reaction score
15,240
ALL of mine locked in 2nd. My 83 G20s 700r4, the 92 4L60 I replaced it with when it had the TBI 350 and my 97 Express van 4L60E.

At WOT? All of my 700R4/4L60 trucks would lock in 2nd at light throttle when manually selected but that's it. The 1500 in my sig would lock 3rd WOT around 70+. Dually is good to down around 58. I keep forgetting to bump that down.
 

L31MaxExpress

I'm Awesome
Joined
Apr 21, 2018
Messages
5,890
Reaction score
7,539
Location
DFW, TX
At WOT? All of my 700R4/4L60 trucks would lock in 2nd at light throttle when manually selected but that's it. The 1500 in my sig would lock 3rd WOT around 70+. Dually is good to down around 58. I keep forgetting to bump that down.

The early carb 700r4 had to have a couple of inches of vacuum to lock in 2nd or 3rd gear but locked regardless of vacuum in 4th gear. The 92 4L60 controlled by the 92 TBI ECM would lock about 45 mph in 2nd or 3rd at anything less than 99.5% TPS. The 97 had WOT 2nd gear lockup only, no part throttle lockup, that came on at 50 mph.
 
Joined
Jan 21, 2020
Messages
20
Reaction score
23
Location
CA
Don't worry about the 4L60. I have a 700R4 similarly built that was intended to go behind a small block. But I came across a good deal on a 454 and went with it, expecting to grenade the 700 and switch to a T56. Nearly 20 years later the 700 is still going. That's in a 67 C10 with 500 ft/lbs, a 3.73 with a locker, and drag radials. Just don't abuse it and don't let it overheat.
 

badco

I'm Awesome
Joined
Jun 20, 2020
Messages
298
Reaction score
181
Location
oklahoma
I know of a few 4l60e holding up to 800+rwhp for couple years now without issue. Its all about the person building it and what his experience is in. Guy that does mine has alot of experience and done alot of r&d with the 4l60 and is only one i trust even on daily driver 60s.
 
Top