Timbren Rear Suspension Enhancement System

This Rear Suspension Enhancement kit were so easy to install, I was almost sure I missed something.
They installed in less than an hour. I was able to place my floor jack under the ball mount to raise the rear end enough to remove the old mounts and simply install the new ones.
Hooked up my 28' rv to my Silverado 1500 and they worked as advertised. No front end sag and I feel safer towing it.
Customer service helped me find the right product I needed without dishing out a lot of cash!817554

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While I have sold this vehicle since this review to my neighbor, she has told me she loves this product when she pulls her rv. I now have a 34 ton pick up and purchased a set for it. I am very satisfied with the Enhancers i purchased for it!

Frank R - 06/19/2021

115721

I have a 2018 GMC Sierra 1500 pick up truck (elevation package) in which I added a 3.5 inch ROUGH COUNTRY KNUCKLE LIFT KIT with Front Struts. The rear distance between the bump stop's metal cup just under the frame and the the rear axle is 8.25 inches with an empty truck bed and a quarter tank of gas. I gave the professional this information on my truck and what I needed; they e mailed back the kit with only 1.5 additional spacers on each side of the truck, Ok. I still came up with 2.25 inch space with an empty truck bed on both sides. I feel More TIMBREN PRODUCTS WOULD be SOLD if websites carried information All together for the average people to buy at their finger tips. It would have been easier for me if the following were all grouped together for my truck :
TIMBREN Rear Suspension Enhancement System
TGMRCK15S (that has 3/8 bushing) which is actual about 4.5 inches not 5inches in
height.
FOR TRUCKS with LIFT KITS spacers are required with the same 3/8 bushings

1 inch spacer (that has 3/8 bushing) A25723-90AHOO
1/2 inch spacer (that has a 3/8 bushing) TA25722-90POO
I required an additional 1 inch spacer on both sides than I was e mailed. It would also be easier if I could buy the additional bolts grouped with my additional 2.5 spacing on both sides of my truck on the web site, than going to the hardware store. I would pay the additional cost. So all together for my 3.5 ROUGH COUNTRY LIFT, I required 2.5 inch spacers on both sides with the 4.5 height kit which = 7 inches . I haul my 4 wheeler in the bed and broke a level spring years ago. On other occasions I place fire wood in the truck bed. TIMBREN is the way to go, it will be there when I put weight in the bed of truck; be it a 4 wheeler or wood. Friends of mine have air bag systems that leak over time and are much more in price. You can not go wrong with TIMBREN. When installing, remove salt and sand near top of original bump stop bolt, apply PB blast wait 10 minutes use a breaker bar with easy removal. Go to the hardware store to get longer bolts. When installing have to jack up the back of the truck under the towing package to get space to use tools to add new TIMBREN PRODUCTS.990665

Awesome for hauling four wheeler in bed and for hauling load of fire wood in the bed, no broken leaf springs and no sag

Joe - 03/23/2022

135206

From Mickey Mouse to Mighty Mouse in minutes. Pulling a 7700lb travel trailer with a 2013 Silverado w/ tow package and h/d cooling. Even with W/D hitch truck was bouncing uncomfortably. The Timbrens were an instant fix. Dips in the road are no longer a problem, and I think the sway control in the hitch seems to feel more solid as well. Unloaded ride is unchanged except for really major dips (and Texas roads have a few). If you are like me and take your truck to places your Mom would not recommend, a good underbody wash and glasses to catch any falling junk during the install are highly valued 307541

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Still a happy camper after a year, and rolling along comfortably. Towing time has increased and timbrens still smooth.

Larry S - 10/17/2017

29491

I just installed these on my 2021 GMC Sierra 1500 AT4. It was really easily done and only took .5 hour total. Because the AT4 is slightly lifted I did use the spacers review separately. I am towing a pretty heavy 2 axle horse trailer with a tongue weight between 6000 and 7000 pounds which the truck can handle. When I hitched up with the original bump stops the hitch dropped 4", the frame over the rear tires squatted down 2 and 3 quarters " and the frame over the front tires lifted 3 quarters". After the installation the hitch dropped only 2 and 3 quarters", the frame over the rear tires squatted down 1 inch" and the frame over the front tires lifted . Test drive went well with the same smooth ride with no load as there is no contact. Pulling the trailer went just perfect, no sway due to the trailer design, and the load was very stable with very little bounce.1082556

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by: Christopher05/06/2022

It's okay. I believe I'm going to replace it with an air bag system though, as currently every time I hit a bump the springs make the small gap to the top of these and I'm always hitting the bump stops.1294722

You mentioned that when hitting a bump a gap appears above the springs. Would be able to send a picture?

-- Jenny N - 05/09/2022

138667

There is always a gap above the springs, they do not contact the leaf spring while the truck is resting. It is just small enough of a gap that any bump I do hit makes the leaf spring contact the Timbren jounce spring, which has the same sound effect as hitting a bump stop.

-- comment by: Christopher - 05/09/2022

138668

My apologies as I was thinking that you meant that there was a gap at the top of the Timbren bump stop verses at the bottom between the bump stop and the springs. Of course, there should be a 0.5 inch to 1.5 inch gap and some people feel like it creates a stiffer ride when the truck is not loaded. I think this is what you are experiencing. I would recommend taking a look at part # AL89388
Air Lift LoadLifter 5000 Ultimate Plus Air Springs w/ Internal Bumpers - Stainless Steel - Rear Axle
$559.94 for your 2021 GMC Sierra 1500 with 4 WD. There are a few tech tips to consider with this kit. It will not fit with vehicles equipped with Adaptive Ride Control or the AT4 models.

-- Jenny N - 05/09/2022

138670

Much bouncier ride than anticipated after installation. I followed etrailer’s recommendation in choosing them but I’m wondering if air shocks would not have provided a more acceptable ride.1447803

by: Vince12/16/2022

They did there job to help level out the truck when hauling however the ride was rougher than I preferred so I opted for airbags instead.1485705

Added these Timbrens with two 1" spacers on each side on a 2011 GMC Sierra with a 2" lift. Fit great, easy to install. Was more work getting old bump stops off than installing the new Timbrens with spacers. I did need to get 2" longer bolts than what was included to complete the install, but that was to be expected.488613

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I have a 2014 Silverado 1500 and 24’ gooseneck weekender horse trailer. I just got the trailer and the guy I got it from recommended the Timbren’s to me. When I first dropped the trailer on my truck empty it squatted me 4.5” in the rear. The trailer weighs just under 5,000 pounds empty. When I first pulled the trailer empty I wasn’t sure about the Timbren’s they seemed really bouncy on my road. My road is not the smoothest road though. This past weekend I loaded 3 horses into my trailer and traveled about 1.5 hours away and I was blown away at how well my truck drove and handled fully loaded. With the Timbren’s my truck barely squats now. The trailer rode a hundred times better loaded with horses, which most big trailers ride bad when empty anyway. As far as driving with no load at all the truck rides just like normal. However if you hit a big hump in the road sometimes it will be enough to make it hit the Timbren’s and gives a little jolt. As far as recommending I definitely recommend these especially if you have a 1/2 ton truck and pulling a fairly heavy load. 656849

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I can't wait to use these and see how they actually work with my 29' x 7.5' wide snowmobile trailer.

For reference to those with an AT-4 GMC, I have a 2020 and with a 1/2" spacer and the timbren (it was actually only 4 1/2" tall, not 5" like the images showed) have about 1.25" gap between the bottom of the timbren and the axle stop when unloaded. I was under the impression that the timbren itself was 5" based on the image in the kit on the website, #tgmrck15s, so I'm a 1/2" shorter than I wanted but I will run it for a while and see how it looks when loaded with my trailer before going any thicker with a spacer. 777214

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Real nice product. Added them to my 2019 Silverado to better support my 6000 Lbs Travel Trailer. They are a big improvement over the stock bumpers.1086648

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Received yesterday (quick shipping!), installed today on 2015 GMC Sierra 1500 4WD Crew Cab short box. What a difference between the Timbren's and OEM bump stop from GMC. Installed for towing large travel trailer. Used floor jack under rear hitch to raise up truck to get enough room for socket to install bolts. Use 10mm socket to remove OEM bolt & bump stop, use 17MM socket to install new bolt and Timbren. Very east installation process. 319774

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I have a 2018 Sierra and these Timbren are terrible. They are way too hard and when you hit a bump they slam hard on the axle. I plan to put my originals back on.1400823

We offer a similar product that might work better for you. The SumoSprings # SS45MR
SumoSprings Solo Custom Helper Springs - Rear Axle
$324.99 is made of a softer material that will provide a ride thats less harsh than what you would get with the Timbren product.

-- Mike L - 09/15/2022

147976

Etrailer expedited the package early due to returning customer. Parts delivered in double packaged boxes. Installed in 1/2 hour after fighting the old rusty bolts. Have not had a chance to load test yet. Will give another follow-up review after truck and trailer are loaded.78488

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by: Cory05/30/2022

I actually found that airbags worked better for my truck and trailer. I ordered those from you as well. May I return the Timbrens for at least partial store credit?1306896

I will have our Customer Service team reach out to you.

-- Jenny N - 06/02/2022

141062

Great product easy to install, took me longer to take the tire off and on than install the product. I hooked up the truck to the trailer and before it stood at 39 inches and when hooked up it dropped to 37 1/2 from the floor to the wheel weld. Overall ride is comfortable with an empty truck load. Purchesed Sunday and was delivered by Wednesday. Great product 518566

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The supplied bolts are too short. Finding the right bolts added to time to do the install.

The jounce springs are 1/2 inch from axle. I'm sure the ride will be very harsh even when not loaded...1445802

Even using equalizing bars, I was experiencing "motorboating" when towing our travel trailer. I've had several air bag setups in the past and have always had to add air daily, so I bought the pair of Timbren suspension enhancement blocks.
Mounting took about 20 minutes.
The Timbren blocks stopped the "motorboating."
Another benefit, is my ride stays as factory without messing with air pressure at all.
Also, now I'm able to move my travel trailer short distances without installing the equalizing bars at all. My pickup stays nice and level.
808766

The Timbren blocks are working out great! The only negative is that there is only a couple inches of freeboard travel brfore the axle contacts the blocks. When there is no load, bumps like speed bumps are a bit harsher than before. I guess that is to be expected though. Even with this slight increase in unloaded harshness, I still give this product five stars.

Mark V - 06/07/2021

115070

I installed this product to help level my 2014 GMC 1500/4x4 when towing a 18ft trailer. They work great and yes I would buy them again. However it will stiffing the ride of your vehicle with no load. If you do not use your truck a lot to carry or pull loads you may not like them. They work just as instructed by the company. Took me only 15 mins to install and a good looking product.170614

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Good customer service poor shipping box came open1285933

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I will have our Customer Service team reach out to you.

-- Jenny N - 04/21/2022

137289

Good quality and I liked the installation videos.1451641

by: Steven05/30/2022

2017 GMC Sierra

Installed on my 2017 GMC Sierra 1500 for towing my camper. It’s a bit bouncy but definitely gives me more lateral and controlled ride with my 5300ish lbs camper. I installed myself and was fairly easy. Overall satisfied with the product.1306901

I think that they are awful. I was told that I couldn’t return them. Upon me purchasing them you did not have the item I was specifically looking for and I spoke to one of your salesman who recommended these and said they were the same thing. Which they are absolutely not. So I would say I am totally displeased not necessarily for the product but for the lack of knowledge from the salesman don’t really know if the product is in good working condition because it’s not the product I was looking for. So now I’m stuck with something I can’t use.1361179

Thank you for your review! I am sorry to hear that this suspension enhancement system is not a confirmed fit for your vehicle. I have sent your information over to our customer service department for them to better assist you.

-- Katrina B - 08/25/2022

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by: Tyler09/23/2021

I purchased these about a year ago and installed on my 2005 Silverado 1500 2wd. I have pulled many trailers with these and they really help the truck not sag so much. The worst part is if you partially load it just right, each bump you hit is HARD since the axle smacks up against these instead of compressing them.1160891

I put these on a Z71 1/2 ton truck. I found a gooseneck horse trailer
with living qaurters 33' long total and when the dealer hooked it to my in bed hitch the truck dropped about six inches told too much trailer for my truck they suggested air bags never heard of timbren
I installed the timbrens went back to dealer this time test pulled you
would think its a 3/4 ton truck now only 3" sag bought trailer pulled it home thanks timbren! great product saved me from bying a different truck dealer thinks it will start selling these!47330