truck shifts hard, tranny trouble, opinions please

[causalitist]

this site is awesome, been sharing ideas with you guys for 2 years now.
hopefully some of you can give me your opinion on a truck related problem.
i have a 1998 S10 4.6L 100k miles, auto transmission, rear wheel drive.

it shifts hard into 2nd gear, a nice kinda jerk, i minimize this by letting off the gas at around 10mph when it shifts, i've been told its no big deal, but am concerned. i bought the truck like this last fall.

besides this the rest of the gears shift smooth and it drives fine if i drive it normally.

however, if i really gas it, let the rpms climb high going 50mph or so, and then LET OFF the gas just slightly, it revs up really high like in neutral, engine is basically "free wheeling" as if no load on it.. aka like in neutral...

if i let off alot this doesnt happen and it goes into the gear it should.
if i continue to floor it, it continues to haul ass like it should.

this only happens if i really gas it for a bit and then back off a tad.
normal driving will not cause it to do this.

it has correct fluid level, new trans filt.

i'm really worried as i paid good money for this truck and if the trans is going out i want to get rid of it.

local trans shops dont tell me jack, just quote me a price to pull it completely apart.

i really hope someone knows about this stuff and can give me an idea of whats wrong, how bad of shape it is in.. this has to have happened to thousands of other transmissions and i figure someones gotta have an idea of whats wrong.

thanks alot guys!!

[topsites]

Well, you could pay the $100 to have a diagnostics done at Aamco thou I did and they just told me what I already knew :laugh:

Change the trans fluid and filter!
Absolutely, this would be my first step, new fluid and what have you but every 10,000 miles is the DIY interval, 20k for shop changes.
It's messy but I prefer DIY so I can see what the stuff looks like (and inspect and clean the pan myself).

Then it could be a rubber grommet or some brass washer needs replacing, translation: something loose in the linkage...
Or a solenoid or some electric sensor in the side of the tranny...

Check and see if you can find the transmission mount, it might be broken.
If so, replace it.

And take it easy, my Dodge likes to stick in gear when I gas it too, yes, stubbornly.
Nothing more that's inexpensive I can do that I know of, just have to drive it nice.
Sux but such is life.

[causalitist]

thanks, i dont mind it, i just need to know if i should be worried it'll go out completely on me.

im torn between just driving it and maybe it wont break, and bringing it into a shop to have it fixed for like $500- $1200

thanks for your response, anyone else out there see this type of behavior from an automatic??

[mverick]

Well this has been my experience.

Have a 97 1500 GMC 350. It has shifted hard since new. They said, it was that the splines on the drive shaft needed to be greased. They did that and it was soft. Once it wore out, it shifted hard again.

I think it's BS. But it's lasted for 10 years doing the same thing and never had the tranny worked on.

My 91 did the same thing.

When I mean it shifts hard. I mean on light throttle it feels like someone just rearended me. I mean HARD. Chirps the tires on occasion. That hard.

Oh, it's towed boats and trailers it's whole life. And, No other problem other then the hard shift.

But, I don't think it's the same tranny as yours. Might be though.

I kinda like it.:)

[topsites]

On the one hand I'm glad to hear I ain't the only one with these malfunctions.

On the other I would find out what is the difference between you fixing it now and having it fixed later (as in, if it totally craps out). Obviously I can't tell you what to do but it might not be that much more if you just drive it, I would still want to find out just in case there's a thousand dollar or more gap... I don't know, it could be a rebuild is right in line with what you're going to pay now, or it might be a ways out there, I haven't a clue but it might be useful information help you reach a decision (or not lol).

I'm going to look into adjusting some shift mechanism as well, both the dodge forum and the manual mentions it just I hate fooling with something I'm not familiar with... I'm the kind of guy if it ain't broke don't fix it, wouldn't be the first time I went tearing into something and it ended up costing me a whole lot more than if I had just let it be.

[causalitist]

awesome, thanks alot for your opinions, thats great to hear your truck shifts hard too .. in all gears or just into 2nd?

[mverick]

awesome, thanks alot for your opinions, thats great to hear your truck shifts hard too .. in all gears or just into 2nd?


Mine only shifts VERY hard into second. It's tight shift into third.

[KTM]

Topsites, if you have Dodge make sure you adjust your tranny bands, that is usually the problem when Dodge's don't want to shift. I just bought one last month with a "bad transmission" bought it cheap fixed it then sold for a profit.

[khouse]

A firm shift is what you want. A smooth shift will wear out the clutch packs faster. I used to install shift kits in tranny's to firm the shift up. If it shifted very hard in all gears I would suspect the accumulator. But it's only 2nd gear so that can be ruled out. Now the freewheeling effect would possibly indicate the direct clutch seal or clutch plates are going bad. But I can rule this out because your other gears hold fast. So this leads me to a possible dirty and sticking valve body. I would install a heavy duty shift kit. This way you get the valve body and spools cleaned. Then the shift kit will better time your shifts. It has been many years since I worked on cars. We used to use Transgo shift kits. They can be bought in many ranges of shifting up to full race options. Also if this doesn't work your kit will not be wasted if you choose to rebuild the tranny.

[ALC-GregH]

causalitist, the trans in your truck is a 700R4. It sounds like it has to much throttle pressure. This can be adjusted at the throttle linkage where it hooks to the throttle body. The cable is located on the lower part of the cable bracket. The cable end has a adjustable end on it with a spring all tied onto the end of the cable. You'll see a metal push tab with a small hole in the center on the tab. Push in on the tab with whatever you can use (finger, screwdriver etc.), when the tab is pushed in, you can slide the cable housing in and out on the bracket, you'll want to slide it towards the throttle body. After the cable has moved in, you can release the tab. At this point, you lowered the throttle pressure and need to re-set the cable to bring the cable back out to the proper length. All you have to do is get inside and push the gas pedal to the floor (truck not running) you'll hear a ratcheting/clicking noise, that is normal and your done. Test drive it to see if it helps. If it's the same, you can push the tab and move the cable 1 click at a time in until it shifts alittle softer. If it still does it, it might have worn/sticking governor springs.

Hope this helps
(25 year mechanic)

[topsites]

I fixed it!!!

Easy money :laugh:

As for the trans band adjustment I'm not questioning this, it should be done every 24,000 but it's not something I have done before and I am 100% sure if done wrong it will do more harm than good, so I left this alone thou I was about to that point to want to try it.

But instead I got up underneath the HOOD to first find the throttle-to-trans cable so I could check the linkages, there was a little paragraph in the manual about this so I thought, why not?

I found the cable (it's not the throttle, watch out for the cruise control too) there was a third cable and it was on the opposite side, this went down towards the bottom and not through the firewall so I assumed this was it. I then pushed the linkage back and forth manually and found it didn't seem to retract like it should, so I went up underneath and found the linkage on the transmission attached to a cable, a spring on the other end... Once I put my hand on it to move it (find out why the cable isn't acting right) I found the linkage mechanism was stuck in about the halfway position!

That is, it would move dandy from halfway out, but it appeared it would never move back to the idle stop correctly, instead stopping at about that halfway point. I could get it to move to the idle position by hand, but it wouldn't do it on its own. So I did move it to idle by hand and left it there, stepped inside the cab and pushed the gas to the floor, then released it. Went back underneath and sure enough it was stuck about halfway again!

So, I sprayed solid amounts of Wd-40 all on that thang, activated it back and forth a few more times manually...
More wd-40, more moving back and forth, until it was coated and dripping and I was sure it had got a nose full.
Then I stepped inside the cab and with engine off I slowly pushed the throttle pedal to the floor and let it back up several times.

Got back underneath, lo and behold the linkage had returned to the correct idle position... Started the engine, took it for a test-drive, worked great! I could drive it NOT normal and it shifted like it's supposed to.

Thought I would pass this on, also check make sure the spring isn't broken (if yours has one).

Other notes: My truck came from Boston and has spent most of its life in New Hampshire... Although I'm from VA the entire underside of this truck is coated in light amounts of rust. This is likely due to road salts they spray up north but down here we're not used to dealing with this so this presents some unique problems.

It sounds like it has to much throttle pressure. This can be adjusted at the throttle linkage where it hooks to the throttle body.

Yup, yup.
This would also explain why it would work fine at either very light throttle or very heavy footing, but not in between and why it would stick after I let go of a slightly heavier foot.

[ALC-GregH]

good to hear you got it fixed.

[khouse]

Glad you got it fixed. Good job Greg H! Since it only shifted hard into second I didn't suspect the throttle linkage.