[cruzcar]

I"m contemplating replacing the transmission in my '03 Intrepid. The passenger side axle shaft is flopping around. Vibrates really bad on acceleration.
Anyway, a salvage yard will sell me a low mileage trans. However, they say the "transmission must be reprogrammed by a Chysler Dealership".
I've done some forum/internet searching and I'm thinking a reprogram is not necessary. The trans is from a 300M.
Any thoughts on this??

 

[peva]

There's normally some radial play in the passenger side tranny stub - it's floating in a bushing, not a pre-loaded bearing. Is an axle joint bad causing the vibration?

If your Trep has a 2.7, gearing will be different (unless trans is from a 300M Special). If your Trep came with 3.2/3.5 and the 300M is not a Special, gearing will be the same.

 

[cruzcar]

Ooops. left out that detail. Got an '03 SXT with the 3.5L H.O. engine. The seller only indicates "300M" is the donor car.

As for the radial play, I checked some 'treps in the junkyard and they do have that play. Of course, I have no idea how many miles are on those cars. Mine is at 220k miles. I've checked other high mileage front wheel drive cars and the inner CV joint has no play. I don't understand how that setup in the Dodge would NOT vibrate. Yes, I understand the concept of floating bushing but still doesn't make sense to me. I have the Right axle and outer CV joint removed, don't see any obvious problems. They will get replaced regardless.

 

[Ronbo]

If it's a standard 300m it has the same gearing as your SXT. Only the 300M Special has the the 2.7L gearing.

 

[peva]

Hopefully the vibration will be gone with new axle. Of course you also need to rule out tire, wheel, hub bearing, and brake rotor issues.

 

[cruzcar]

It's on it's second set of new tires. Bought another wheel (I hate donut spares) and after tire rotation, problem is still on the right front. On it's second set of new rotors. Strut rod bushings were replaced. The shock struts are original, though. New struts may dampen the vibration, but, I don't think that's the cure. Do have a new hub bearing to install

 

[cruzcar]

About that floating bushing. There is an adjuster on the passenger side of the transmission. Turning that adjuster sets the pre-load on the differential bearings (transmission disassembled only procedure). Could adjusting that help with the wiggle in the output shaft or we talking about two different things?

 

[Ronbo]

Have you tried replacing the CV Axle on that side? Your symptoms are common with a bad axle.

Your car isn't lowered is it?

 

[peva]

About that floating bushing. There is an adjuster on the passenger side of the transmission. Turning that adjuster sets the pre-load on the differential bearings (transmission disassembled only procedure). Could adjusting that help with the wiggle in the output shaft or we talking about two different things?

The carrier is in preloaded bearings, but the stub rides in a bushing within that.

Question for OP: Is the vibration that you are experiencing possibly the wheel oscillating due to bad tie rod? It is very common for the inner tie rod bushings to wear out every once in a while on these cars, and when that happens, the wheel can bang back and forth at certain speeds. Thought I'd mention that just in case.

 

[peva]

duplicate - deleted

 

[peva]

Below is a blowup of the differential. The short shaft (3) is the passenger side. Notice that the carrier is supported on bearings (22 & 23). The inboard ends of both shafts plug into the pinion gears (9), and the shafts float in bushings (7 & 14) not far from the pinions. Notice that the driver's side (long) shaft (20) has additional support of a bearing (19) in the tranny case near its outboard end. The only support the short shaft has is the bushing and the pinion gear - and at very close spacing. That's why the short shaft seems to move around a lot more than the driver's side shaft when you shake it with your hands.

(Realize that the differential carrier is rotating with the shafts on straight and level driving. Only when you turn a corner is there very small speed difference between the shafts and their bushings (differential action) - so the bushings and shafts don't see much wear, but they do have some clearance play from the factory.)

 

[cruzcar]

I did check the tie rod play by grabbing tire and trying to twist it side to side. Didn't notice any tie rod play. Good question.

The car has not been lowered or altered.

peva, the pics and diagrams didn't load. I see that broken image icon.

The vibration is tremendous on acceleration. At steady speed there is a very mild to almost not noticeable vibration.

Complete axle/cv assembly should be at the house before the weekend.

 

[peva]

...peva, the pics and diagrams didn't load. I see that broken image icon...

Fixed (I think).

I believe the classic symptom of a bad inner axle joint is vibration while accelerating. (Bad outer joint causes popping noise when turning.)

 

[cruzcar]

Yes, that fixed it. Thank you very much.

By the way I have read the posts on this "Why LH cars normally have what appears to be excess play in the passenger side stub shaft....
I haven't read Chewievettes transmission overhaul thread, yet.

No popping or clicking noises from the driveline while turning or accelerating.

 

[peva]

Yes, that fixed it. Thank you very much.

By the way I have read the posts on this "Why LH cars normally have what appears to be excess play in the passenger side stub shaft....
I haven't read Chewievettes transmission overhaul thread, yet...

Bottom line, he was skeptical of the info. about play in the passenger-side shaft being normal, so he replaced all parts associated with it. After all was said and done - all new parts, bearings properly adjusted - it had the same amount of play as before the rebuild. I was glad he did that because it confirmed my theory on the play being unavoidable with the design.

...No popping or clicking noises from the driveline while turning or accelerating.

You mention vibration in your symptoms. My point was that *IF* the axle is the problem, it is likely the inner DOJ that is the cause. But of course, you're replacing the whole axle, so it doesn't matter.

 

[peva]

So did the new axle fix the vibration problem?

 

[cruzcar]

Thanks for checking up on the situation. Haven't had a chance to replace it. We've had rain and mid 40's temps every weekend. This weekend is forecast to be 62 degrees and partly sunny. All my car maintenance is done outside on the driveway. Maybe I'll get it swapped Saturday.

 

[cruzcar]

Replaced passenger side axle/CV joint assembly. Problem solved. Accelerates smoothly.

Now for the details.........
Removed the inner CV hub with a slide hammer. 4 whacks and it popped off.
Trans. stub shaft had radial play, about 3/8" in all directions. Serviced diff. fluid while I was there.

 

[peva]

Far out, dude!! Glad you didn't go down the rabbit hole with an unneeded diff. rebuild or something.