So I'm at the local "bench racing in a big parking lot" spot and a guy with an LS1 Z28 drives up. We talk for a while and he starts telling me about what he has done to his car and he mentions that he got rid of the 4L60E "because it's garbage" and put in a TH350.....I didn't want to refute b/c I honestly don't know either way but I didn't think the 4L60E was bad at all....what's the deal? Does he speak the truth or is he just BSing???

 

I wouldn't necessarily call it garbage, but it's definitely not that strong, and it has been problematic for some. I've seen a guy go through three 4L60Es in a year on a bolt-on car. I've also seen a couple guys with heads and cam (both LT1 and LS1) running stock 4L60Es.

If you plan on pushing a good amount of power, a turbo 350 or 400 swap is a good idea, as those two are proven performers and can take serious abuse (but they're also 3-speeds, so an OD might be necessary for a non-race car.)

There's some places that now claim to build strong 4L60Es, but I'm not sure how strong (or if they last.)

 

That's his opinion and if he likes it that way, then so be it.

For a race car it probably is not the best good choice, but for a daily driver with mods it works fine.

And if the stock tranny is not strong enough, there are quite a few places which will make you a very strong 4L60E that can handle quite a lot of horsepower.

TS

 

I was using one with my 383 with a d1sc no problems now granted no passes at the strip but none the less it is not a race tranny for the street it is a nice tranny

 

I blew 3 4l60E's in one summer. 2 of which were supposed to handle over 450 hp. I'm not saying that the 4l60 is a hunk of scrap, but I have had alot of problems with mine. I know a few guys that have ran them with luck. Its just like anything on a car, some have luck, some don't. I switched to a pro built th350. I've been running it for 2 years and it runs perfect. No overdrive, but at least I can drive my damn car. I don't mind not having overdrive. Its all in what you want. I also should tell you that I did'nt have much money in the swap. I bought the tranny, converter, and install kit for less than 1 4l60E rebuild. The swap was very easy to do also.

 

Years ago when the TH350's were in everybodys vehicle, the same stories about how they were junk and the TH400,s were the way to go. The same today, not very many people know how to make these units (700R4/4L60E) last, and they have to go to something earlier, to get the results they want.