Engine/Transmission (1994 - 1998) automatic transmission

[jimk]

Does the transmission have a life span, that the planetary gears and bearings become work hardened, or do they. Is there a life span on the transmission parts to where it would be better to buy a new transmission. The problem is that a new transmission wont yield much with with out a lot of modifications to make it last, different valve body, torque converter, etc. So by the time you add the price of a new transmission and then the modifications that would be a huge amount of money.

If you have lets say 100k miles and the transmission needs a overhaul how much life does the hard parts have? What about the bearings in the planetary gears? How do you inspect for gear failure other than wear. What is the cycle life of the gears, hubs, shafts etc.

My father had a 89, I believe, Dodge diesel and when he pulled the automatic apart to inspect the slipping clutches the out put shaft was twisted. Now this is a stock 160 hp truck that would not spin the tires unless it was in low in the transfer case so is there a life span on the hard parts?

Thank JimK

 

[jimk]

automatic

Since I have gotten no response to the question, may be that it is not asked properly, I don't know.

I was at a seminar a couple of years ago a fellow told me that it is better to start with new transmission and do the valve body and torque converter,

I have thought that if the transmission had lots of miles then what a person could do is to, for a 94 or 95 truck like mine is to find a 98 truck that is wrecked, low mileage and get the transmission to build a hybrid transmission. Or at least the overdrive section.

JimK

 

[LSMITH]

The hard parts if serviced properly, not abused, and not subjected to massive power all the time will live a LOOOOONNGGGG time. 500K miles is not out of the question at all. You will likely go through some bearings in that time and stuff like that, but the gears and other hard parts themselves are fine. Clutch packs can live for that long too if not slipped and shifting is correct. New bearings are darn cheap, they should be replaced anytime the transmission is opened IMO.



There have been mods made to the oiling circuits and clutch packs for the OD in the 94 and 95 trucks that bring them to the level of the later trannies. I would not waste my money on a later transmission to rob parts from, and no way would I buy a new transmission to upgrade. That would take a very expensive option and make it insanely expensive.



If an auto is setup right, treated right, and problems taken care of right away they will last a LOT longer than people think. Some of the hotshotters are getting over 300K out of an auto transmission without any work other than fluid changes and band adjustments. The stock transmission that comes in these trucks is WAY WAY WAY tougher than it gets credit for, internal leakages take out a few in a hurry, people that don't know how to operate one take out a few, and pretty soon all you hear is that they are all weak junk. Not true at all.



If you want to upgrade your transmission take it and get it done. No need to buy another or worry about things. Pick a good builder and go for it.

 

[shaft]

LSMITH... ...



Dang..... A true voice of reason in the wilderness!... ... I had gotten so used to seeing this :-{} over transmission's it certainly is nice to see someone with a reasonable and valid point of view on a rather tired subject.

 

[wsmalley]

I agree... .



I only have mild engine work in mine... . 100rwhp worth or so, and all I have done to my transmission is to put a shift kit in and up the line pressure, this was about a month and a half ago and she ain't let go yet. this is with 125k on the original transmission, although it may have been rebuilt before I bought it. Otherwise the drivetrain is all stock. SOON TO CHANGE THOUGH WITH A SUNCOAST TRIPLE-LOCK TC and VBOo.

 

[inarush76]

trans life span

LSmith has some good points.



JimK

You probably have a much better than even chance that your trans would not need many hard parts, if any. If your trans still has the aluminum front planet then the steel one is a definite step forward. I have seen a fair number of rear annulus carriers worn on the rear thrust surface as well as output supports(OD piston retainer) that are worn by the intermediate shaft often from owners not allowing time after start up for the lube circuit to charge before taking off. It is not unheard of for a trans with well over 100K to need no hard parts. It does have some to do with how trans is maintained and used as well as the quality of fluid. Hope this helps. If you have any other questions, email me.

-- email address removed --



James Northum

DTT builder/installer

 

[jimk]

transmission

Thank for the advice James. My truck has 90k miles on it and it has never given any trouble except for the annoying TPS switch.

The switch has given me a dose of ... . and I am tired of that.

Regards Jim