4t65E problems after axle replacement

pontiac
grandprix

#1

I have a 2002 grand prix gt with under 100k. When I first got it there was a leak in the pan for the trans and it got ~3 qts down on fluid before I realized. Did not seem to be any damage and its driven for 20k miles since, but it’s the only reason I can think my trans would break upon removal of an axle. I recently attempted to replace the axles and now power is not going to the wheels. It is currently up on stands in my yard and while in park I am able to turn the drivers side axle freely while the passenger side axle is locked to either direction of rotation. When i put it into gear it reads my speed as about 10 mph despite no wheel rotation and the car being stationary. I am very close to just changing my transmission but was going to attempt putting it all back together for the hundredth time and trying to make it work again before I drop the trans. I feel like I am just missing something stupid due to lack of experience and there is an easier fix than a new trans and was just hoping for a little advice from someone with more experience than I. The transmission is a 4t65E


#2

We had 2 gt’s and 2 gtp’s. Changed trans in gt with no issues. The gtp has a HD version and I think the pass axle is shorter than the nonhd. Can you compare old/new axles?


#3

It sounds like the transmission isn’t mating up to the axle for some reason. So it’s turning, but not turning the axle. As long as you didn’t hear any weird grinding noise, should be fixable without messing w/the transmission. The instructins I’m seeing for replacing the axle shaft say to insert it into the trans, then verify the retaining ring is properly seated. Did you do that? The instruction say apparently you just pull outward on the inner cv housing (not the shaft). If it pulls out, you know it wasn’t properly seated. Makes sense …lol … The only other thing I can think of (other than the good advice offered above) is something got damaged in removing the old shafts. The procedure calls for using 3 special tools to do that. I’m not sure what those tools are though. On my cars I’ve always been able to either sort or pry them out of the trans, or use a slide hammer tool. What technique did you use to remove them?

I looked up the tools, and two are just the normal slide hammer, but there is one that goes on the end that appears to be specially shaped to hold onto the inner cv housing so the force is equally distributed all the way around. I doubt you had that tool. But I doubt not having it is the reason for you symptom if you otherwise used a slide hammer approach.


#4

I actually just took a utility strap wrapped it around the axle at the base and jerked it out with a big bar tied to it. I popped the clips off the axle and transmission and it seems like the axles are in the way they are supposed to now so im going to take them out, take out my struts so i have full access to them and try and properly seat them with the clip on and see if I’m good. Thank you so much for your help


#5

The instructions make a point of saying the force to free the axle from the transmission should be applied to the inner cv casing, not to the axle shaft. I presume this is b/c the inner cv isn’t designed to handle a “stretching” force. Since you didn’t re-use the old shaft/inner cv presumably, shouldn’t pose a problem.

If I had that problem, as an experiment I’d install the shafts into the transmission, but just let them dangle free on the other end. I’d rig them up so they could turn without hitting anything, maybe suspending them on some bailing wire. Then I’d start the engine, put it in first, to see if both shafts turned or not. Putting a mark on the axle to show how far it goes into the transmission hole when it is presumably “seated” would make sense too. If they seem to seat ok, and they rotate when not connected to anything at the wheel end, I’d suspect the replacement shafts are either defective or the wrong length. Getting replacement half-shafts of the wrong length from an auto-parts store isn’t an uncommon report here.


#6

The inner CV joint is called the plunging joint

This is what allows the axle to get longer and shorter as the suspension goes over bumps.

The outer CV joint is called the articulating joint

This is what allows the axle to turn with the wheels.

Tester


#7

That must be why the instructions say to not pull on the axle shaft, apply the force on the inboard joint casing instead. If you pull on the axle shaft the whole ass’y just moves outward like on a spring, and won’t result in enough force to pull the inboard joint splines out of the transmission. Here’s a Popular Mechanics show and tell link about how to replace an axle shaft if anybody’s interested. It presents it in a simplified way for purposes of explanation, doesn’t cover some of the problems I’ve encountered doing that job. But its worth a watch.


#8

Remove the left axle and inspect the differential to see if the side gear has dropped, look for mating splines for the inner C/V joint. If OK, install the axle then remove the right side axle and inspect the differential side gear.

With some differentials the side gears can drop out of position if both axles are removed at the same time and there is the slightest movement to the differential.


#9

I had been pulling from the inner cv so I didn’t tear the axles but I was replacing them either way so it didn’t matter. Replacement axles were wrong. Ground some metal off of the passenger side which wasn’t going in right but it was metal from the axle not the tranny and I’m doing a drain and fill and cleaning my magnets and changing the filter so hopefully it won’t mess anything up. The majority was pushed out because the axle was not seating and I mopped up what I could out of the transmission and hopefully the magnet takes care of the rest. No big pieces of metal just shiny gray fluid. No shavings in fluid from the dipstick or from popping the other axle out so it seems like it didn’t get too deep. As of now looks like it’s all good thanks everyone for the advice.


#10

Thanks for the update OP. Getting an incorrect part is a common half-shaft replacement problem. Good for you for properly diagnosing it. Sounds like you are on the right track. Best of luck.