D8R trans problem?

Robert0769 · Feb 16, 2019

I purchased a used 1998 D8R. It has the torque converter rebuilt about 8,000 hours ago and the engine, trans and turbo rebuilt 2,000 hours ago. It seems strong, pushes a mountain down hill. Up hill kinds sucks but dirt is heavy and no slipping.

Here's the problem. If I hold the brake and shift to forward or reverse, then let go of the break, it does nothing. I then tap the brake and it engages and moves.

Having to release the break to engage the transmission on a steep hill sucks.

Trans oil level seems correct.

Any ideas?

Thanks!

Nige · Feb 16, 2019

As usual to start with - Serial Number......?
May be the service brake pedal switch sticking but without a S/N to know what powertrain control system you have it's pointless going further.

Bls repair · Feb 16, 2019

Never worked on one of these . Sounds like the brake. is hanging up . When on the flat ,shift from forward to reverse and back. without using the brake ,any problems. Try shifting into neutral a split second before applying
Brake,any problem.

Robert0769 · Feb 16, 2019

7XM00754

If I shift forward, reverse, forward without break it shifts fine.

Robert0769 · Feb 16, 2019

I will be there in a couple hours and try shifting neutral before applying brake

Nige · Feb 16, 2019

Ok, so not new enough for a service brake pedal switch. My thoughts: -

1. Get the floor plate up and clean/lubricate the brake control linkage. There are lots of pivot points & clevises on it.
2. Once it's lubricated, go through the adjustment procedure (attached). Have a good look at the condition of the 183-1136 return spring that fits behind the brake pedal assembly, it may be "tired". A new spring would be around $55.

newguy2k3 · Feb 16, 2019

Sounds like the limit switch in the brake pedal housing may be sticking.

Junkyard · Feb 16, 2019

I’m with Nige, if it’s old enough it’s more or less mechanical linkage under there I’m betting the linkage is stiff. Is it lever steer with the flip up brake safety lock?

Dave Neubert · Feb 16, 2019

Can you pull up on the pedal and make it work. I agree it sounds like sticky pedal or linkage

JPV · Feb 18, 2019

Sounds like the bearings on the end of the cross shaft for the brake linkage on the front side of the firewall need a shot of lube like Nige says, l am betting it moves when you pull up on the pedal. It doesn't take much. You don't need to pull the floor plates, I reach in behind the motor from both sides with a can of good penetrating oil and give them a shot, also hit the throttle shaft while you are there. There may be a better way but that works on ours.

Robert0769 · Mar 6, 2019

I checked the trans fluid dipstick again and noticed it was more pretty thin so added more trans fluid and I think that did it. It hasn't had shifting problems anymore. I cleaned up the linkage just in case.

Thank you for all your help

D8R trans problem?

Robert0769

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Nige

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Bls repair

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Robert0769

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Robert0769

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Nige

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newguy2k3

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Junkyard

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Dave Neubert

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JPV

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Robert0769

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