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Riffraff Diesel Performance Inc, Engines - Supplies, Equipment & Parts, Eagle Point, OR


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John Wood 4R100 Valve Body

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John Wood 4R100 Valve Body

We offer modified valve bodies from John Wood Automotive because it is our experience that they are one of the best offered in the industry.  John Wood has been building transmissions and valve bodies since 1983 and has a reputation for strong attention to detail, quality before quantity and excellent customer service. 

A JW Valve Body will help to firm up shifting, while keeping the shifts crisp and not banging into gear.  Also performs shorter shift duration, which decreases heat generated and reduces slippage and wear on the friction plates. 

While the valve body can be used with stock programming, we suggest DP-Tuner if you are thinking about upgrading.  Jody and John work closely together to make sure that you will get the most out of your transmission.

Please note that there is a 3 week window for core returns.  If the core isn't recieved back 21 days from customer reciept then your core charge will be forfeited down to 50% and after 30 days you will be charged the core retail cost of $150.

Fitment Details

1994-2003 4R100 Transmission

This part is unable to be returned after received.
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Product Reviews

Showing reviews 1-10 of 14 | Next

  1. Worth it 5 Star Review

    Posted by on Dec 8th 2017

    Just had my transmission rebuilt, figured I throw this valve body in (after a recommendation from my tuner PHP tunes). Before the transmission went in for the rebuild I switched over the tunes to the modified valve body tunes with the stock valve body (which was expected using modified valve body tunes with the stock valve body) it was very sloppy and non existent shifting and there was definitely slippage. After the rebuild and valve body though was a different story. Not too firm and not to smooth of a shift and no slipping, just smooth shifting. All in all I'm very impressed with the valve body, worth every penny.

  2. Best Mod I have done 5 Star Review

    Posted by on Oct 4th 2017

    This is by far the best mod I have done to my truck. Took about 30 mins to swap it over and have the truck back on the road. Shifts are much faster, its goes in to gear with no slipping which is very nice and defiantly made the truck faster due to this. Trans temps with an empty load have been on avg 20 degrees lower. Will be the first mod I do on my next truck!

  3. Worth Every Penny 5 Star Review

    Posted by on Sep 20th 2017

    Istalled and it works as advertised. Long slow shifts are gone, now it has nice firm shifts. Easy istall nothing to it. It works well with my PHP Hydra. Money well spent.

  4. No more shifting problems! 5 Star Review

    Posted by on Jul 30th 2017

    This was one the best purchases I have made. I installed a php hydra and had some shift flare. This solved the problem shifts are clean and crisp. I highly recommend

  5. Like usual great product 5 Star Review

    Posted by on Sep 5th 2016

    Riffraff never lets me down another great product!!!

  6. Great upgrade 5 Star Review

    Posted by on Jun 23rd 2016

    I haven't had a chance to tow with it yet. But just normal driving you can feel the difference in the shift. It's not a long shift anymore. It's fast and smooth.

  7. Great product 5 Star Review

    Posted by on May 31st 2016

    The transmission shifts much quicker without being harsh, an easy project with Riffraff's instructions. As always, great service from Riffraff.

  8. Very well done 5 Star Review

    Posted by on Oct 16th 2015

    It has firmed up the shifts and the transmission seems more responsive.

  9. It Does Make a Difference 4 Star Review

    Posted by on Oct 16th 2015

    I replaced the stock valve body that came on a new 4R100HD with this JW product. The stock VB was very, very smooth and subtle on the new transmission. After this product was installed, I can feel the really quick shifts. It is not harsh, as others have noted, but each shift is felt. So far, so good.

  10. Installed on my 1999 Fleetwood motorhome. 5 Star Review

    Posted by on Oct 14th 2015

    The transmission has 44,000 miles on it but I felt the shifting was too slow and possibly prematurely wearing the clutches. This took out all the slop, firm but not jarring. Easy to install, I just had to get an inch pound torque wrench.

Showing reviews 1-10 of 14 | Next

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