[kstmbowtie]

i have a 1980 el with a 350/350. the trans started slipping. it started with 3rd and the longer i drove it the more the other gears were slipping. i let it cool down for a few hrs ad was able to make it back home. i have a friend that has a th400 he will let me have for $150. and i have a 4l60 thats been sitting out in the dirt for about 4yrs. not sure if i should try to use one of these. i have people that will help with any modifications needed, just dont know if there are better options. what would be required for either to work? thanks for any imput.

 

[84elcoconquista]

May try the 400, just because the other ome has been sitting out. I dont know if the crossmember under the tranny would have to be modified?? You could ask trannymike?

 

[ccc]

400 s are horsepower hogs,they use 35 more hp just going down the road.if its not a 10 second race car its a waste,the 700 is a better choice.the 700 can use the stock 350 crossmember you just need to shorten the mount pad about 1 in. both will need the drive shaft shortened.the 400 will need a whole new end of the shaft and yoke because its yoke is bigger,the 700 uses the same yoke as a 350.pull the pan on the 700 if its not full of rust or trans debris i would run it plus the overdrive will save you fuel and with its 3.06 first gear will make it quicker on the take off compared to the 400s 2.48 first

 

[kstmbowtie]

The 4l60 is out of a 98 silverado. Doesn't it shift electronicly? How does that work?

 

[rtatwk]

The 4L60E is just what the 700R4 changed to be. Case is the same...If you took an older 700 and rebuilt it properly it would essentially be a 4L60E. This one does require the drive shaft to be 3" shorter and crossmember moved obviously. Also wiring to get 12 volt back to the tranny for lockup on the overdrive. I'm not sure about those modifications listed above to use the 400. There is a diagram showing all to compare lengths and such somewhere in this same forum. Try searching through the thread about lockup quick fix or something like that. Get it going soon Jess!

:beer:

 

[kstmbowtie]

correct me if im wrong. if i use the 4l60e and dont hook up the electronic plug, then do i basicly have a 3 speed with out over drive. or are the electronic parts more involved?

 

[old_coot]

correct me if im wrong. if i use the 4l60e and dont hook up the electronic plug, then do i basicly have a 3 speed with out over drive. or are the electronic parts more involved?

Its a lot more involved----If you don't do the electronics you will have one forward and one reverse gear----limp home mode and thats all.

 

[kstmbowtie]

i was hoping you wouldnt say that.

 

[rtatwk]

Nope! Without the 12 volt hookup you just don't have lockup. Its a (guess) 300 more RPM'S at highway speeds...Not much difference around town. Gees the lockup has been out of whack on my 2004R and I just unplugged it and still drive all over the darned place!

 

[kstmbowtie]

i just got off the phone with a friend that retired from the transmission buisness and he said if i buy the overhaul kit and a new tourque converter, then he will help me rebuild it. so i just have to wait until the 10th :nanawrench:

 

[ccc]

if you have a 98 trans you dont have a 4l60 you have a 4l60 e which does need a computer to shift.in your first post you said you had a 4 l60 not an e sorry for the misinfo to tell which you actually have the 700/4l60 has a 4 wire plug on the same side as the shift linkage,a 4l60e will have a round 20 wire plug on the pass.side if you were closer to idaho i would trade you if you do in fact have an e trans

 

[rtatwk]

CCC I am no where near the transmission expert. Perhaps there were further changes as to wiring in later gen Transmissions. The 700R4's had original issues with wrong gear takeoff and also no overdrive at times. The Sonnax upgrade and other use of 4L60 parts (Corvette springs and servos) can transform these into a kick ass transmission. If later models required electronic type shifts ,or all servo, that is completely different for sure. I am quite certain that one with the 4 wire plug will still run fine unplugged...Just no lockup. I'd just like to figure out why the 4 wire plug has 3 wires and only 2 of them seem to mean anything. I am only trying to help a young member friend out here. Tranny Mike and this other member who has posted some serious info that has been transferred to the Articles and How to section will have the answers...MichaelJ or something like that...All good info!

 

[jlcustomz]

For the meantime , a bottle or 2 of lucas trans fix may give you a little more use from yours.

 

[TrannyMike]

I just saw this. When I get home I'll give you the correct information. Old Coot is right though. Gotta get back to work! :beer:

 

[kstmbowtie]

well im not compleatlly out of a ride. i have an enduro, but this great fl weather were having lately makes it a lil soggy by time i get to work. lol. Im greatfull for all of the imput. Thanks guys.

 

[kstmbowtie]

i just tried to edit a post and i dont think it worked, so if it comes up twice please forgive me. i wanted to clarify on the friend thats going to help me do the rebuild. its for the th350 thats in my car already. so if all else fails then im going to go that route.

 

[TrannyMike]

If you're on a budget go with the 350, it's a great trans for an El Camino. The 400 isn't worth the trouble to convert, and as stated does use HP to run it. If you want overdrive you'll have to pass on the 4L60E, it won't work. A 200-4R is the most popular choice of overdrive trans because of the gear ratio change from 1st-2nd gear. 700's are OK, but the when it goes from 1st-2nd the ratio change is bigger and lower HP/torque motors don't perform as well.

OK, there are a few things that need to be corrected here. There is no way to build a 700(4L60)and make it a 4L60E. They have internals that will interchange, but that's about it. The cases and valve bodies are completely different and nothing can be done to change that.

"Tranny Mike and this other member who has posted some serious info that has been transferred to the Articles and How to section will have the answers".That other member got all the info from me. He posted what I private messaged to him and it became a sticky. That's a good thing though, I don't care that his name is on it.

"For the meantime , a bottle or 2 of lucas trans fix may give you a little more use from yours." If you are going to build your trans I wouldn't do that. It's beyond a chemical fix, and you may damage hard parts driving it more and that'll cost you more cash.

A 700 or 4L60E only run 1 servo and that can't be changed(more servos). The Corvette servo kit does work on both transmissions though and improves the 1-2 and 2-3 shifts. A Transgo stage 1 or 2 kit is a good choice or a Sonnax Sure Cure kit can be installed in either trans, but are completely different kits for the 700 and 4L60E.

The electrical connector does have 4 ports for wires but all only use 3 of them. 1 is a 12 volt wire that's always hot when the motor is running, the 2nd is the ground wire, and normally is only grounded by the computer. The 3rd wire depending on the year is for a temp sensor signal or pressure switch signal to the computer so it knows if it's the correct time to ground the circuit and turn on the lock-up solenoid. There are 4 different configurations and the 3rd wire is where the differences are.

A 4L60E has 12 pins not 20 at the connector. Besides a computer a 4L60E requires a few sensors that are inputs to the computer to develop a "shift strategy".

I am the tranny expert here, but never want to show anybody up. I just want to help folks out and hopefully I do. :beer:

 

[kstmbowtie]

thanks for the helpful info. i will be pricing rebuild kits for the th350, and a new tq converter.

 

[SSelkokid87]

All hail the Mighty Trany King! Thanks for the info Mike! Interesting fact's to know!

 

[P8riot]

Mike, I wish I lived in Cali now. I would bring my tranny to you for rebuild/install. Unfortunately I will be doing it all myself, with a lotta help from my friends here!