I'm not sure if it's a coincidence, but after replacing both cv axles the trans acted as it was slipping. Sometimes shifts from 1 to 2 hard and never shifts to 3rd or downshifts. It seems like it goes into neutral and stays that way until the car is cut off and restarted. Gets up to around 3.5 to around 4k before it does this. Any ideas of what this might be? Any ideas would be appreciated. Let me know if any additional info is needed.

 

sounds like a dumb question and im not questioning your ability, but are the axles seated all the way in?

 

Yes, they're fully seated. This actually might be a stupid question but would they seat if they had a different spline count or maybe a different length of the part that slides into the transmission? It shifted fine beforehand so it just seems strange.

 

First check your fluid level.
Turn the engine on, let it warm up, and slow down its idle.
Check the transmisison fluid, pull the stick, wipe it off, reinsert fully pull out and check again. The fluid should be within the hash mark.

When removing/installing the axles did you make sure not to damage the differential seals? If these seals are damaged the trans will not leak when parked flat but will leak when accelerating or parked on an incline with the nose up. Look for fluid sprayed onto the exhaust/rubber hangers down the right side of the car. It will cause a mess down by the right side rear wheel and rear suspension.

Did you compare the new axle to the old axle length?
The inner CV joint is a sliding joint, this allows the needed change for effective length of the axle during suspension travel. If the axle was assembled fully compressed to its shortest length then the axle will not easily lengthen. Once the inner CV boot straps are installed it will cause pressure build up in the boot under compression or a vacuum under extension. With that said, if the axle was assembled 'short', then the inner stub axle may be pulled out of the differential just enough during extension of the axle. Once the car settles back down from the shift event the axle may slide back into the splines enough to re-engage the differential and power the wheels. Although, I would think this would make a bit of a racket.

The easiest way to tell if the problem is trans slippage or axle slippage would be to watch the tachometer/speedometer when the event happens. If both tach and speedo rise but the car slows down then you know its a problem between trans and wheel(axle). If the tachometer revs and the speedometer does not change or slows down, then their is a problem between engine and axle(trans).


Axle splines are ,individually, pretty much the same size. The more the spline count the larger the axle diameter is.

If the axles diameter was smaller than the transmission or hub, it would be very noticeable. One the fit would be fairly sloppy, and two you would probably never have been able to torque the stub axle nut on the hub.

 

Thank you both for the replies. Mike, fluid level is good. Seals were also not damaged. To be completely honest I didn't compare the old to the new. I had a friend at a shop order them and gave the old one for core. Wasn't exactly thinking about it at the time. I do know they are definitely fully seated. I don't have a way of really checking my speedometer. I've tried changing out the vss but no luck with it.