Community Forums

Chieftain27 · 04-19-2022, 01:14 PM

Here’s what goes down when I try and move my rig. I drive a 1986 Chevy p30 454 engine winnebago. It’s automatic.
I turn it on and after letting it run for a minute or so I bring the idle down.
I put it in drive and nothing happens no sound of idle change and no gear locking into place. It sounds as if it’s still in park.
I put it in neutral and I hear a change in idle a normal relaxed engine sound.
I put it in reverse and nothing happens either. Other than an idle sound that’s not the neutral sound. Basically it sounds like it’s in park again.
I repeat every so often until it finally shifts into reverse.
It ALWAYS shifts into reverse first.
After a few more minutes of patience and try’s I get it to engage into drive. Engine sounds like it should when in drive.
(10-15 minute process)
Now when i finally get it moving it sounds like my breaks aren’t fully releasing from my back left rear tires and I don’t have full power to the gas pedal.
Now I’m currently camp hosting for the next two months and haven’t put it on the road yet to see how it reacts at higher speeds.
I’m really hesitant to do this as I don’t want to cause more damage.
If i turn it off for about ten minutes it’ll fire right up and drive with the rubbing sound and lack of full power in drive. It reverses better than going forward. Just a reminder.
Your help is greatly appreciated.

PJStough · 04-19-2022, 01:19 PM

The first thing I would do is check the transmission fluid level. Do you know how long it has been since the fluid and filter has been changed? It is possible that the filter is plugged from lack of service, and not allowing the fluid to be sucked up into the pump. If a change of fluid and filter doesnt help, the next place I would expect to be the problem is the torque converter. How many miles does the RV have on it?

dizcom · 04-19-2022, 01:27 PM

Quote:

Originally Posted by PJStough

The first thing I would do is check the transmission fluid level. Do you know how long it has been since the fluid and filter has been changed? It is possible that the filter is plugged from lack of service, and not allowing the fluid to be sucked up into the pump. If a change of fluid and filter doesnt help, the next place I would expect to be the problem is the torque converter. How many miles does the RV have on it?

These were my first thoughts also. Your problems seem unrelated (brakes and transmission). You probably have more than one problem.

Chieftain27 · 04-19-2022, 01:50 PM

Quote:

Originally Posted by PJStough

The first thing I would do is check the transmission fluid level. Do you know how long it has been since the fluid and filter has been changed? It is possible that the filter is plugged from lack of service, and not allowing the fluid to be sucked up into the pump. If a change of fluid and filter doesnt help, the next place I would expect to be the problem is the torque converter. How many miles does the RV have on it?

It is time for a fluid/filter change. Fluid looks good though nice and red. Levels are good and the mileage is 71.4k

153stars · 04-21-2022, 08:57 PM

It's been a while, couple things pop into mind, Vacuum modulator on trans. Issue with trans valve body. Old GM trans have had the plate that adjusts valve body with teeth clicks into roller on flat spring. The nut that holds it in place just fall off or slip because of loose nut . Fixed a couple friends as well.

twinboat · 04-22-2022, 04:50 AM

Plugged filter will cause delay in engagement. Fluid needs to warm up and thin out.

Problem is, the filter gets plugged up with friction material from warn out clutchs, and bands if used.

May be time for a rebuilt transmission.

TXiceman · 04-22-2022, 08:39 AM

Number one is when was the last time you had the transmission fully serviced with fluid and filter change? I had the transmission serviced at 40,000 miles on my gas motorhomes and trucks. Transmission service is a lot less expensive than transmission repairs. I also used a synthetic transmission fluid that met the manufacturers specifications.

Start by checking the transmission fluid level per the owner's manual for level. The fluid should also be pink with no spell of burning or dark color.

Ken

outlawten5 · 04-22-2022, 08:49 AM

I would first jack up the rear and make sure the rear wheels spin freely while the trans is in neutral, engine off. Next I would check the trans fluid level and smell if burnt. Is it a 3 or 4 speed automatic?

D Gardiner · 04-23-2022, 10:25 PM

You should have a THM400. As others have stated, replace the fluid, and filter. Plus check for leaking vacuum to the modulator, or a bad modulator valve. Once fixed, drive it more frequently to keep the seals, check valves and servos from sticking.

You also want to check for a sticky kick down cable.

As to the brakes. Not sure if you have the front disk rear drum, or the 4 wheel disk chassis. Dragging brakes can be caused by restricted rubber brake hoses, defective drum/shoe return springs. Rusted backing plates (drum brakes). It can also be caused by rusted brake caliper sliders. On our '96 454 the caliper sliders were all slightly stuck from rusty sliders, which cause caliper dragging after brake application.

Quote:

Originally Posted by Chieftain27

Here’s what goes down when I try and move my rig. I drive a 1986 Chevy p30 454 engine winnebago. It’s automatic.
I turn it on and after letting it run for a minute or so I bring the idle down.
I put it in drive and nothing happens no sound of idle change and no gear locking into place. It sounds as if it’s still in park.
I put it in neutral and I hear a change in idle a normal relaxed engine sound.
I put it in reverse and nothing happens either. Other than an idle sound that’s not the neutral sound. Basically it sounds like it’s in park again.
I repeat every so often until it finally shifts into reverse.
It ALWAYS shifts into reverse first.
After a few more minutes of patience and try’s I get it to engage into drive. Engine sounds like it should when in drive.
(10-15 minute process)
Now when i finally get it moving it sounds like my breaks aren’t fully releasing from my back left rear tires and I don’t have full power to the gas pedal.
Now I’m currently camp hosting for the next two months and haven’t put it on the road yet to see how it reacts at higher speeds.
I’m really hesitant to do this as I don’t want to cause more damage.
If i turn it off for about ten minutes it’ll fire right up and drive with the rubbing sound and lack of full power in drive. It reverses better than going forward. Just a reminder.
Your help is greatly appreciated.

Argosy · 04-27-2022, 06:30 AM

Change the trans fluid, do as suggested and pull the left rear drum. It's going to be a pain to do, most likely the will be a lip on the outside edge from wear as it sounds like your shoes are dragging. Brakes are designed so forward motion helps them engage, that's why it seems to drag more going forward than when you back up. Turn the drums turned to get rid of the lip. Drive it for a few miles then change the tranny fluid again. You only change about 5-6 quarts at a time and depending on the pan, converter, and cooler it will hold 12-16.