Car's a 2k t/a with H/C and supp mods, makes around 400rwhp/350 tq through a stock 4l60e and a PI 3800 stall. Well yesterday i noticed that 2nd and 3rd are slipping in normal driving conditions, (gets worst as mph's climb and car wont go above 50-60ish) but sometimes when i go wot in 1st they'll have an abrupt engagement and might go in.. idk if it would be trans or TC. It also has a squealin noise from a start when i give some gas and sometimes from a low roll if i step on it, what does it seem to be the prob?

 

A bad trans oil pump will cause slippage in all gears, could be intermittent and can cause squealing noises.
A pressure gauge connected to the trans will quickly determine whether this is the problem; any trans shop can do that for you.

 

thanks ^^^ for your reply MRvedit, i'm considering having a local tranny shop rebuild the 4l60e and this are the parts he will upgrade/advertise:
Transtex master kit with Borg-Warner Clutches.The kit includes high energy clutches, the gears, the steels, bushings, rubbers, seals, Teflon rings, and gaskets.
New Kevlar band (Kevlar is used on boats instead of fiberglass because it's stronger and lighter. The extra wide Kevlar band is very important because it controls 2nd and 4th gear. The vehicle comes out of first gear hard so you'll need the Kevlar band to hold second. Fourth gear is just as important because it's the most used gear so the strength of the Kevlar band holds it strong and firm.)
New Seal Power filter
29 Element Sprag (the sprag has 29 bearings on it that hold the one way clutches so they won't break.)
Blocked off accumulators (this is a common trick of the trade we block off the accumulators to give nice firm crisp shifts working with the corvette servo, 500 boost valve, and shift kit.)
Aluminum Corvette Servo (Works in conjunction with the Kevlar band to help hold the force of the gear changes by raising line pressure to give fluid quicker flow and no hesitation between shifts.)
Hardened Sun Shell The Beast (Much stronger than a stock sun shell its reinforced where they commonly strip and then the metal is hardened so it won't break the two most important gears 2nd and 4th and even reverse
Z PACK ( controls 3rd and 4th gear comes with18 high energy clutches instead of the factory nine and is designed to hold up to high h.p. and heavy highway vehicle cruising for long periods of time.
5 Pinion Hardened Planetary designed for pulling heavy loads or serious h.p. activates in first gear and with 5 pinion planets turning instead of four it increases your odds of not breaking if your mudding, towing or playing tug of war.)
13 Pump Vane Assembly designed for faster fluid flow creating a firmer and quicker response during the shift patterns)
Stage 3 Shift Kit(different then a stage two shift kit a stage three shift kit has stiffer springs for firmer shiftiness and different holes for valve body plate giving it an even firmer shift.)
Blocked off accumulators (this is a common trick of the trade we block off the accumulators to give nice firm crisp shifts working with the corvette servo, 500 boost valve, and shift kit."

DO THESE PARTS UPGRADES SEEM LEGIT??? eventually i want 550-600 out of the trans am and he said it will hold,, anyone??

 

Sounds like a good tranny build, how much is he going to charge you? I would shop him against RPM and FLT who will basically be doing a similar rebuild to what he is saying. You may also want to keep in mind that RPM and FLT are well known to be expert builders of 4L60Es. Your local guy may be good, it sounds like he is, or may be just able to talk a good game. You may want to talk to some people who he has done some performance rebuilds for. One other factor to consider is, can you swap the tranny yourself? If not you may be best to deal with a shop like this guy that can do the rebuild, and the installation for you. That way there is only one person responsible if somthing is not correct. Best of luck with it.

 

i was quoted 1100 if i drop her off at the shop.. I don't have time/knowledge or tools to drop the tranny myself.

 

If the local builder is used to building with these parts, it sounds reasonable.
Just a few comments:
1. If you use a wider band, you MUST use a new Reverse drum or the wide band will be quickly ruined.
2. DO NOT block off accumulators!!! That is for kids with a 250HP engine that want the tires to chirp on shifts. I would suggest the Transgo HD2 kit which many people here recommend and have experience with.
3. I'm not sure that the Z Pack is the best choice. I don't think any of the sponsor use it or would recommend it. I have heard that 400HP is about its limit.
While the combo is good, it does sound a bit dated to me.
Some of the sponsors list what they put in their trans. I know that the PATC site (not a sponsor and not my favorite) has an excellent list of their preferred parts.

 

Alright, mrvedit said it but not as forcefully as I will: you need to avoid this shop. If he is blocking off accumulators he is retarded and is not to be trusted. If you are planning on putting it behind 600whp you need rpm or flt. Period.

 

A local privately-owed trans shop can be very competent and conscientious, but generally have very little experience with non-stock transmissions.
For a rebuild kit, I would recommend something from www.trutechtrans.com which also has excellent, detailed tutorials listed on their website home-page.
Jeff is the owner, easy to reach and very helpful on the phone. He can sell you a very good rebuild kit with everything a good local mechanic would need.
BTW - I was also going to use the Kevlar band I bought for of my builds, but several mechanics told me not to. While very strong, they require more clapping force, more than even a Vette servo can provide in a high HP car. (Or so I was told.)
If one of the sponsors Performabuilt, RPM or FLT wants to sell you a rebuild kit, I'm sure that would be very good too.

 

thanks bud.
I wanna clear this doubt off my head (seems logical) but would like to hear from someone else. With a tranny going downhill will the numbers at the rollers be low?? Two weeks after i bought the car i took her to a local dyno and made 2 passes, the first one was cut short at 5800, she only made 337 tq and 389rwhp. The 2nd run he couldn't get a tq reading (dunno why) and spun her to 6500 and power went up to 408. On the add when i was looking to buy the car it was listed she made 425/455 tq and ran according to the guy 11.6's...


(adding mods to sig)

 

Here are some vids of the car hittin the limiter while running
http://youtu.be/tIE7KS9dYfo

http://youtu.be/9GNoSMuNTXU

I was told issue was in the tune but i'm leaning to think it was actually the tranny on its downfall???

 

Tranny has a 3800 PI stall converter, there shouldn't be any issues reusing it on a rebuilt tranny? Is there anything i would need to replace? thanks

 

Need to get the converter cleaned.

 

Took her for a quick test run, and in 1st, she roars and pulls like a train then i manually went into 2nd and same, it just seems to be slipping in 3rd gear or if im just reg driving in D after 40ish... Could be the 3-4 band or clutches are burned?
When i'm just driving and she starts slipping i go into 2nd gear and she'll pull fine in 2nd all the way up...hmmm

 

???...

 

From your description, you are experiencing a common problem with the 4l60e - a worn 3/4 clutch that is now slipping. Sounds like time for a rebuild. I have listed some of my performance parts suggestions above.

 

thanks mrvedit, i heard on another thread that if the 2-3 shift hits the rev limiter it could be the converter??? i hope not, ($$$) cus just the tranny alone has to wait i can't imagine if i need a converter too

 

No, a high-stall converter will slip a bit more than the stock one and thereby cause the rev limiter to be hit slightly before the stock shift-MPH is hit. That is one reason high-stall converters need a PCM tune. No one here can be sure from just a description, and I don't have the experience to ever "be sure", but I think your converter is fine and that the 3/4 clutch to worn and slipping.

 

thanks, i bought the car with the PI stall, and was told the car was tuned 5yrs ago, so i'll imagine Dan@Masport would had tuned the pcm for the stall back then. here's a link to the vid but dunno if it was stalled at the time, i can't quite make out if i hear a cam and consequently been stalled for the cam..
http://m.modernhemi.com/forums/showthread.php?p=8337962

 

i'm getting a hell of a deal for a used 4l60e,($200) and i'm going to swap trannys. Other than cleaning the PI 3800 converter, is there anything else i need to do to the oem tranny, to make it work? Someone told me i need a shift kit, is that so? Once the tranny comes off the car, l'm going to slowly build it with performance parts for down the road....

 

you need to have the converter cleaned but other than that as long as everything looks good swap it in.... but be warned a stock 4l60e is on borrowed time with a motor like yours. even bolt on ls1's will do the stock 4l60 in