Need trans tech input

[Rmck85]

Hey guys, I've been having some trans issues. I have a 98 1500 4x4 reg 8' with 5.2 and 46re. When I got it back 2 years ago, I had to replace gov pressure solenoid and sensor. I did a trans service while in there, adjusted bands by the book, and replaced fluid with mopar atf4. It's been good until last fall. I was towing my atv and trans overheated. I pulled over and atf was really high on the stick. I let it cool down and continued with od off. I wasn't even towing 1500 lbs. I checked linkage, seems right. Full tension on WOT. I know check valve can clog going to cooler. I replaced the complete lines and hoses from radiator to transmission. Also replaced radiator. I did another trans service. Slight clutch material in pan on magnet, no chunks. Filter still seemed clean, but replaced it anyway.

I have it filled properly. It seems to be running around 225-230* on highway in OD, no trailer or load other than me. Outside air temps in the 30s/40s f.

I watched scanner, target pressure and actual pressure are on until it goes over 45mph. With OD on or off, target is listed at 101psi and I'm running about 63psi.

Also I noticed from a stop, in gear, when you let your foot off the break, it hops. Goes away under acceleration. If I floor it on an onramp or off the line, it shifts smooth, no slipping or banging. It feels like a tank though, like it is under powered or pulling a load. I also noticed air bubbles on the stick when checking fluid level. Is this a sign of a pump problem, torque converter issue, or something else?

Any and all input will be greatly appreciated.

 

[dudeman2009]

Thats a tough one. I'd suggest a fluid and filter change and a band adjustment. I know that the book says to do it one way and there is a guy on here called Dapepper who says to do it another way, I think its final turnback is 1 7/8ths vs 2 7/8ths but i'm not sure. However, Dapepper is right on whatever it is. You'll also want to inspect the band material to make sure it isn't almost gone.

 

[DodgeDude99]

The backing off of the band adjustment screw is going to different on not only years but also the ratio of the band strut.

 

[dapepper9]

After speaking to multiple vendors and trans builders, it's been highly suggested to me to go 1 full turn over spec for band adjustments on otherwise stock transmissions.

Hot running sounds like your converter isn't locking. OD has very low fluid flow through the converter and it's supposed to lock to assist in cooling, longevity, and mileage. If your converter isn't locking you'll run hot and get like 12mpg at 60mph. You can tell if it locks by getting up to speed and watching the tach. Get into 4th gear/OD at about 55. Setting the cruise is a good way to trigger lockup. Watch for a 2-300rpm drop on the tach

 

[DodgeDude99]

Going to tight on a band is a good way to fry it.

http://www.dodgeram.org/tech/transmission/automatic/AT_band_adj.htm

 

[dapepper9]

Going to tight on a band is a good way to fry it.

http://www.dodgeram.org/tech/transmission/automatic/AT_band_adj.htm

Exactly why it's been highly suggested to me to back it off an extra turn lol

 

[DodgeDude99]

My bad, I read your post as going another turn tighter.
I know some guys that adjust them without a torque wrench, which yeah you get a very firm shift....for 5000 miles and the pan is full of band material.

I’m not sure what smells worse, ATF or gear lube. Ones smells like cat **** the other is pungent

 

[dapepper9]

My bad, I read your post as going another turn tighter.
I know some guys that adjust them without a torque wrench, which yeah you get a very firm shift....for 5000 miles and the pan is full of band material.

I’m not sure what smells worse, ATF or gear lube. Ones smells like cat **** the other is pungent

Yeah no i couldn't agree more lol. 72in/lbs if i remember correctly on exact tq spec (check the manual, I'm bad about not using tq specs on many things but i think I'm right on here) and back off an extra turn. Factory spec is a bit tight unless you have high miles on the unit.

I prefer ATF. Gear oil is atrocious

 

[DodgeDude99]

I in the process of rebuilding a 12 bolt for my ‘70 Camaro, I’m pretty sure The gear oil is from the GM assembly line!

 

[Rmck85]

At 65mph I am running at 1800 rpms. 3.55 gear ratio. 245/75/R16 tires. The truck is a ST so no tach or cruise control. I got rpms from my scanner.

When I did the gov press sensor/solinoid I replaced with Mopar factory sensors. I also used a torque wrench when tightening and backed off according to 98 46rh specs, 72 in lbs on front adjustment and back off 2 7/8 turns. Rear band adjustment 72 in lbs, back off 2 turns. I refilled trans with Mopar ATF plus. The band adjustments were probably about 12,000 miles ago. Truck has 174,000 on it. I asked the guy who had serviced it last if he knew if trans was worked on. He thought it was rebuilt a few years back at a trans shop but wasnt certain.

 

[Rmck85]

Well it seems after everything, a tire is part of the issue and the other is a defective u-joint which was just replaced. I noticed the shaft hopping so I thought it was bent. I was going to send it out and felt the rear joint binding. For the heck of it I put another joint in, tested it and the hopping was gone. All that's left is tire vibration.