2001 pt cruiser gears 3.94 or 3.55

dailyslammer · Post by **dailyslammer** » Tue Feb 14, 2012 5:58 pm

i tried the search but i cant find anything on 01s or if i do nobody mentions the differential. i have a 2001 mtx pt cruiser transmission i wanted to know if it was a 3.94 or a 3.55 cause i had my trans rebuilt by brown daub dodge and they cracked the case and never told me and now i need to figure out a trans fast and another question does this trans already come with dif pin blockers?

ThatKevin · Post by **ThatKevin** » Tue Feb 14, 2012 6:49 pm

this is completely unrelated (sorry)

but... I NEED to see pics of your car. Please post a thread full of them

chipdogg · Post by **chipdogg** » Tue Feb 14, 2012 7:58 pm

How much did you pay the dealer to rebuild it?

PT cruisers came with 3.94 final drive. Not sure on the diff tabs, probably not in 2001.

I would NEVER take a 5-speed trans to a dealer to rebuild. It'd be rare to find that any of the technicians were trained on the T-350 since they haven't been made for a car in 7 years. Plus dealers would rather sell an assembly than rebuild something.

If you need a trans rebuilt, let me know. I have been trained by Ed Peters on everything inside the T-350. How to modify, rebuild, inspect, clean, diagnose, etc. I've rebuilt at least 40 of them and have all the Miller special tools to properly disassemble and assemble them.

Hell if you just want your internals swapped into a good case, send me a message. I have a pile of core transmissions. A couple cable bellhousings, and a couple hydraulic bellhousings too.

Post by **occasional demons** » Tue Feb 14, 2012 8:20 pm

As far as diff pin tabs, All I know is the 2001 FSM does not show them in the illustrations. The '04 FSM does. So somewhere in between they came equipped from the factory.

I know my '01 t350 3.55 ratio did not have them.

FWIW, your '01 PT is the same as the R/T MTX. The '02 and newer N/A PT had the .72 fifth gear, which makes them almost identical to the 3.55 .81 fifth gear, for overall top gear ratio.

Edit: So the case is cracked, as in leaking oil cracked? It was hard to tell from your post. It could be read as they cracked it open to look at it.

You plan on using the PT as a replacement?

Most likely your original MTX is 3.55. You will see a noticeable gain in power to the wheels. (If I understand what you posted) Your higway/cruising RPM in fifth is going to be higher.

dailyslammer · Post by **dailyslammer** » Tue Feb 14, 2012 9:22 pm

i was referred to the dealership by a couple local guys with srt4 who had there transmissions rebuilt there and i figured they did a good job so i dropped it off and about a week later it was done. well i finally grab the trans to put it in and notice the case is cracked on the bottom about 4 inches around the bolts and i called them back and they asked me to drop it off. long story short they told me they couldnt do anything cause the cases were known to crack and they couldnt do anything about it but they would give me 20% off a new case and put it together for free. so in the mean time i have the mtx trans from the pt cruiser i pulled for an old car but a 3.94 is gonna suck with boost. thanks for getting back to me though i appreciate it

Post by **occasional demons** » Tue Feb 14, 2012 9:34 pm

First I have heard of a cases "known to crack". I can see it if there was something stuck between the halves, and it was tightened down on it. But I could be wrong...

The thing with a new case, is you have to hope they shim the diff bearings properly, or the output shaft gear, and "ring gear" will wear out rather quickly.

chipdogg · Post by **chipdogg** » Tue Feb 14, 2012 9:36 pm

They are full of crap, these cases are not "known to crack". They only crack if something is wrong. If they rebuilt it and cracked it, they should fix it for free. It had to be put together wrong, they likely forced the bellhousing on by impacting the bolts instead of making sure it was all lined up. Can you shift it by hand easily?

If you want, send it to me and I'll put it in a case I have for cheap. That is a load of bullshit.

Have any pictures of where it cracked?

dailyslammer · Post by **dailyslammer** » Tue Feb 14, 2012 9:41 pm

it almost looks like it was over torqued to be honest with you. the reason i want this trans up and running is because i had dif pin blockers put in, new second gear and third gear, hydraulic bellhousing conversion and the dif was shimmed. its really all ready to go except for this effing crack. i even debated on tig welding it but i dont wanna destroy something inside from the heat. i really need to get my hands on some service manuals and do all this stuff on my own from now on

Post by **occasional demons** » Tue Feb 14, 2012 9:53 pm

You will never weld it assembled together. The oil won't let you, and even taking it apart, and trying to get it clean enough will be a challenge.

Did they use RTV to seal it? If so, I would almost bet they let it cure too long, and it didn't squish, and cracked the case when tightening it.

Or the one bearing in there that needs greased in place dropped when the put the half back on.

Been too long since I did mine, but I know the one bearing gave me fits, until I packed some grease in there to hold it in place. Even then, I was paranoid as hell as I tightened the bolts down. But it is still going 40,000 mile later.

dailyslammer · Post by **dailyslammer** » Tue Feb 14, 2012 9:58 pm

it shifts fine. everything seems the way it should be im really thinking they over torqued it. and theres rtv all over the trans. whats wierd was they put it in a black bag when i picked it up. i never seen that done it was like i picked up my trans from a back alley no name shop. i couldnt have done it cause i was gentle with it i took it right home and set it on a cushion away from eveything in my basement. im just really aggravated right now but im installing this 3.94 now so well see what happens. i might be pming you soon chipdogg. im gonna take that trans and try and make them fix it, if not youll be my savior cause 19lbs boost and a 3.94 are gonna make my new snow tires disappear fast

chipdogg · Post by **chipdogg** » Tue Feb 14, 2012 10:00 pm

Please post a pic.

You won't be able to tig weld the case. It's not pure aluminum like you'd normally weld, it has some silicon in it to help release it from the mold.

You can still use the stuff inside, I can easily swap them into another case and set the preload on the differential. I do it all the time and would only charge you $50 for the case and shipping.

In order for it to crack, something isn't installed right, whether it's the plastic caged bearing or the dowel pins didn't go into their holes straight or something.

And if the dealership knew what they were doing, they'd use the proper sealant.

dailyslammer · Post by **dailyslammer** » Tue Feb 14, 2012 10:08 pm

ill post a picture up tomorrow or maybe later after i get this thing roadworthy again

Post by **occasional demons** » Tue Feb 14, 2012 10:21 pm

High silicon content is to reduce stress cracking when cooling in the mold, and it also makes it harder/more wear resistant. IDK how much of that translates to making it release from the mold, but in a way, it does indirectly, as it holds it shape better.

At any rate, welding it isn't a good idea.

I have seen the bell housing welded where it bolts to the engine, but IDK how well that lasted. That part does not hold oil either.

chipdogg · Post by **chipdogg** » Tue Feb 14, 2012 10:24 pm

Well whatever it's for, I know it's in there and the case shouldn't be welded. I have a couple cores that could use some welding but they are in the scrap pile.

dailyslammer · Post by **dailyslammer** » Wed Feb 15, 2012 4:51 pm

got some good news i got ahold of one of the guys that recommended the dealership and he hooked me up with a free core and had me meet him at the dealership and they are gonna swap everything over for free and have it done by friday afternoon. and by the way this pt cruiser trans is awesome driving through the city but as soon as i hit highway i was doing 80mph at 5000k it was terrible haha. again thank you all for the help i appreciate it

chipdogg · Post by **chipdogg** » Wed Feb 15, 2012 5:24 pm

Good to hear. Make sure they use anaerobic sealant. Loctite 518 or equivalent. Not RTV.

ThatKevin · Post by **ThatKevin** » Wed Feb 15, 2012 6:08 pm

sooooooooo no pics?

chipdogg · Post by **chipdogg** » Wed Feb 15, 2012 6:25 pm

ThatKevin wrote:sooooooooo no pics?

I'd like to see them yet.

Donkeypuncher · Post by **Donkeypuncher** » Wed Feb 15, 2012 6:58 pm

dailyslammer wrote: as soon as i hit highway i was doing 80mph at 5000k it was terrible haha

That makes me think twice about swapping to 3.94, speed limit is 70mph around here.

What rpm would that be with the taller 5th gear?

chipdogg · Post by **chipdogg** » Wed Feb 15, 2012 7:10 pm

http://www.neons.org/tire/speed.shtml

The taller 5th in a 3.94 is almost identical to the 3.55 HD 5th, since it's a .81 in the later 3.55's.

3.55 x .81 = 2.8755
3.94 x .72 = 2.8368

Your revs will be slightly LOWER with the 3.94 and taller (.72) 5th gear when compared to the later 3.55's with the .81 5th.

Although if you get a 3.94 with the .81, that's a different story!

When I do my 4.12, I'll be using the .72 5th to keep it somewhat sane in my magenta. Although highway cruising isn't at the top of my priority list.

a23dranger · Post by **a23dranger** » Wed Feb 15, 2012 7:17 pm

hey daily slammer did you get the pt trans off tom or did he use it in his acr? what are you rocking now since the 00 with vette wheels?

Post by **jonnymopar** » Sat Feb 18, 2012 9:21 pm

occasional demons wrote:As far as diff pin tabs, All I know is the 2001 FSM does not show them in the illustrations. The '04 FSM does. So somewhere in between they came equipped from the factory.

I know for a fact that my '03 did not have them. Must have been '04.

Donkeypuncher · Post by **Donkeypuncher** » Mon Feb 20, 2012 5:41 am

chipdogg wrote: The taller 5th in a 3.94 is almost identical to the 3.55 HD 5th, since it's a .81 in the later 3.55's.

3.55 x .81 = 2.8755
3.94 x .72 = 2.8368

Your revs will be slightly LOWER with the 3.94 and taller (.72) 5th gear when compared to the later 3.55's with the .81 5th.

That makes sense, I never actually did the math. Explains why my 5th gear is only like 500rpms lower than 4th gear.