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Topic: Replacing transmission retarder valve (split from Re: What did you do to your coach) (Read 4901 times) previous topic - next topic

Replacing transmission retarder valve (split from Re: What did you do to your coach)

Replaced Allison retarder valve assembly. See attachment.

Re: Replacing transmission retarder valve (split from Re: What did you do to your coach)

Reply #1 –
Thanks Dick -
Nice shots - so that's wat it looks like.  ^.^d  Something new everyday. ;)

Scott

Re: Replacing transmission retarder valve (split from Re: What did you do to your coach)

Reply #2 –
Howdy Dick,
  Thanks for the information and great photos.. Good job on the write-up.
ttyl,  Dave A

Re: Replacing transmission retarder valve (split from Re: What did you do to your coach)

Reply #3 –
Thanks Dick, that was a great write up.

Re: Replacing transmission retarder valve (split from Re: What did you do to your coach)

Reply #4 –
Thanks from me as well ... just got done replacing this valve as well as it started leaking a bit.  We were able to find one on Ebay for ~$136 (same place / seller as Dick told us about).

The only difference for me from what was posted is that I could not remove the old valve as it hit our transmission cooler when you tried to unscrew it.

I opted to remove 3 of the 4 bolts that held the accumulator to its bracket and just loosen the 4th one.  This allowed the accumulator assembly to rotate down (once you un plugged the wire and air line).  With the accumulator valve rotated I had all the clearance I needed and it allowed me to use all of the existing hardware with the new valve.  Tighten all the fittings, rotate the accumulator back up and tighten the bracket bolts.

Re: Replacing transmission retarder valve (split from Re: What did you do to your coach)

Reply #5 –
(Moved this from the older thread)

Heads' up on an eBay watch item.  This is an older version than the one Dick and we recently installed (we used the 29552377) in our coach.  The body is shaped more like the original, but do check compatibility before buying.  For reference, the Allison p/n on our old (original) one was 29522717.


$99 currently and he has more than 10 available.

Allison Retarder Valve 29547934 Superceded by 29552377 | eBay

Re: Replacing transmission retarder valve (split from Re: What did you do to your coach)

Reply #6 –
The retarder valve was leaking on my 1991 U300 and I replaced it while I was at Foretravel in Nacogdoches a while ago. They tried to look it up on the drawings but the retarder wasn't even on the drawings. They said 1991 was the first year for the retarder and of course Foretravel was the first manufacturer ever to offer a retarder and very few customers ordered retarders that first year. After thinking about it a couple of the guys at Foretravel said they remember my coach being built and they think it was the very first coach ever to have a retarder. Foretravel had to put their own valve on when they built my coach because Allison didn't supply one yet so they used an expensive European valve instead. They still use a similar valve on the pneumatic doorstep of the current Foretravels so that's what they sold me and I installed it in their parking lot ...and it works! haha ...I dunno why I wrote this, I guess cuz it entertained me at the time. It probably won't benefit anyone because I believe Allison started supplying retarder valves shortly after my coach was built so it's doubtful many readers will have the weird European valve.

Scott

Re: Replacing transmission retarder valve (split from Re: What did you do to your coach)

Reply #7 –
Quote from: RRadio –
After thinking about it a couple of the guys at Foretravel said they remember my coach being built and they think it was the very first coach ever to have a retarder. Foretravel had to put their own valve on when they built my coach because Allison didn't supply one yet so they used an expensive European valve instead.

Scott
If anyone ever underestimates the value of the manufacturer still being in business, this is a pretty good testimony....22 year old coach, and the people who built it can help keep it all in working order.

Amazing.....

Re: Replacing transmission retarder valve (split from Re: What did you do to your coach)

Reply #8 –
Scott, GREAT post! Exhibit "A" on why FT is different than any other Motorhome Brand.

Re: Replacing transmission retarder valve (split from Re: What did you do to your coach)

Reply #9 –
Quote from: Steve –
Thanks from me as well ... just got done replacing this valve as well as it started leaking a bit.  We were able to find one on Ebay for ~$136 (same place / seller as Dick told us about).

The only difference for me from what was posted is that I could not remove the old valve as it hit our transmission cooler when you tried to unscrew it.

I opted to remove 3 of the 4 bolts that held the accumulator to its bracket and just loosen the 4th one.  This allowed the accumulator assembly to rotate down (once you un plugged the wire and air line).  With the accumulator valve rotated I had all the clearance I needed and it allowed me to use all of the existing hardware with the new valve.  Tighten all the fittings, rotate the accumulator back up and tighten the bracket bolts.

I went to start up the coach and heard air leaking from the rear. I saw it was coming from this Allison retarder valve assembly. Thanks to Dick's write up I knew what it was and how to replace it. I was getting ready to leave on a Rally and wasn't sure if I could leave it until I returned. I called Mark Harvey and he said just remove the air line and cap it. But you won't have retarder operation.
It did not look like it would come off without hitting but it turned out it was close but a little nudge was all that was needed. I did have to add a nipple to the new one to get it back on. I also bought it from Ebay. (Dick's Source)
As a bonus my Dash gauges show no leaks overnight.
After all those hours under the coach cleaning those dirt ridden ABS valves and spraying for leaks it turns out this valve was the cause. :o
Thanks again Dick for the write up. Learn something new everyday.

Re: Replacing transmission retarder valve (split from Re: What did you do to your coach)

Reply #10 –
The valve on our hydraulic accumulator leaked so badly at one time that we could build no more than 70 psi. The leak came on suddenly. All was OK when we drove to the dump station. We could not build enough pressure to leave the dump station. After I found the leak at the hydraulic accumulator valve, I "adjusted" it with a rubber mallet. The valve has worked fine since. If you have a leak at that valve, you may wish to try "percussive adjustment."