# How to Install Brother TN635 Toner Cartridges? > Learn how to install Brother TN635 and TN637 toner cartridges step by step. Works for all colors, yield levels, and compatible Brother printers. Source: https://support.ldproducts.com/en_us/how-to-install-brother-tn635-toner-cartridges-SJBibY2NWe Last updated: 2026-01-15T04:10:17.694Z **Quick Answer**: To install Brother [TN635](https://www.ldproducts.com/catalogsearch/result/?q=tn635&xid=tmd:blog:pdp&utm_medium=blog&utm_source=ldhelpcenter&utm_campaign=TN635_series:SJBibY2NWe) or [TN637](https://www.ldproducts.com/catalogsearch/result/?q=tn637&xid=tmd:blog:pdp&utm_medium=blog&utm_source=ldhelpcenter&utm_campaign=TN635_series:SJBibY2NWe) toner, open the front cover, remove the toner and drum assembly, replace the toner cartridge, reinstall the assembly, and close the cover. TN635 and TN637 cartridges use the same installation process across all colors and yield levels. For a full comparison—including compatibility, yield options, installation, drum units, and cost-per-page considerations—see our [TN635 vs TN637 Toner Series Guide.](https://www.ldproducts.com/blog/brother-tn635-series-toners/?xid=tmd:blog:pdp&utm_medium=blog&utm_source=ldhelpcenter&utm_campaign=TN635_series_SJBibY2NWe) * * * ## Step-by-Step: Installing TN635 and TN637 Toner 1. **Turn the printer on** – Make sure the printer is powered on so it can properly recognize the new cartridge. 2. **Open the front cover** – This provides access to the toner and drum assembly. 3. **Remove the toner and drum assembly** – Pull the toner and drum unit straight out using the handle. 4. **Remove the old toner cartridge** – Press the lock lever on the drum unit and remove the old toner cartridge. 5. **Prepare the replacement TN635/TN637 toner** – Remove it from the packaging, gently rock it side to side to redistribute toner, and remove the protective cover. 6. **Install the new toner cartridge** – Insert the new TN635 or TN637 toner (Black, Cyan, Magenta, or Yellow) into the drum unit until it clicks securely into place. 7. **Reinstall the toner and drum assembly** – Slide the complete assembly back into the printer. 8. **Close the front cover** – The printer should automatically recognize the new toner. ### Helpful Notes * All TN635 and TN637 cartridges install the same way, including standard and high-yield versions (such as XL or XXL, where applicable). * You can mix different TN635 yield levels and colors in the same printer (same for TN637 if it supports it). * Avoid touching the green drum surface, as fingerprints or scratches can affect print quality. * If print quality issues appear after installation, gently cleaning the corona wire on the drum unit may help improve output. * * * ## Compatible Brother Printers for TN635 and TN637 These instructions apply to Brother printers that use TN635 and TN637 toner cartridges, including: * [HL-L8430CDW](https://www.ldproducts.com/ink-and-toner/brother/hl/hl-l8430cdw?xid=tmd:blog:pdp&utm_medium=blog&utm_source=ldhelpcenter&utm_campaign=TN635_series:SJBibY2NWe) * [HL-L8430CDWT](https://www.ldproducts.com/ink-and-toner/brother/hl/hl-l8430cdwt?xid=tmd:blog:pdp&utm_medium=blog&utm_source=ldhelpcenter&utm_campaign=TN635_series:SJBibY2NWe) * [HL-L8570CDW](https://www.ldproducts.com/ink-and-toner/brother/hl/hl-l8570cdw?xid=tmd:blog:pdp&utm_medium=blog&utm_source=ldhelpcenter&utm_campaign=TN635_series:SJBibY2NWe) * [MFC-L8730CDW](https://www.ldproducts.com/ink-and-toner/brother/mfc/mfc-l8730cdw?xid=tmd:blog:pdp&utm_medium=blog&utm_source=ldhelpcenter&utm_campaign=TN635_series:SJBibY2NWe) * [MFC-L8930CDW](https://www.ldproducts.com/ink-and-toner/brother/mfc/mfc-l8930cdw?xid=tmd:blog:pdp&utm_medium=blog&utm_source=ldhelpcenter&utm_campaign=TN635_series:SJBibY2NWe) * [MFC-L8970CDW](https://www.ldproducts.com/ink-and-toner/brother/mfc/mfc-l8970cdw?xid=tmd:blog:pdp&utm_medium=blog&utm_source=ldhelpcenter&utm_campaign=TN635_series:SJBibY2NWe) * [MFC-EX575](https://www.ldproducts.com/ink-and-toner/brother/mfc/mfc-ex575?xid=tmd:blog:pdp&utm_medium=blog&utm_source=ldhelpcenter&utm_campaign=TN635_series:SJBibY2NWe) * * * ## Frequently Asked Questions ### Do TN635 and TN637 toner cartridges install the same way? Yes. TN635 and TN637 toner cartridges use the same installation steps, including removing the toner and drum assembly and locking the new cartridge into place. ### Do I need to reset the printer after installing TN635 or TN637? No manual reset is typically required. The printer should automatically detect the new toner once the front cover is closed. ### Can I replace only one color at a time? Yes. TN635 and TN637 cartridges can be replaced individually by color, and different yield levels can be used together in the same printer. ### Are TN635 and TN637 interchangeable? TN635 and TN637 cartridges install the same way, but they are only interchangeable in specific printer models that support both toner series. Printers that support TN637 toner include Brother HL-L8570CDW, MFC-L8970CDW, and MFC-EX575. * * * ## Related Articles * [Which Brother Printers Use TN635 Toner?](https://support.ldproducts.com/en_us/which-brother-printers-use-tn635-toner-BkEWkDNSZe?xid=tmd:blog:pdp&utm_medium=blog&utm_source=ldhelpcenter&utm_campaign=TN635_series:SJBibY2NWe) * [Which Brother Printers Use TN637 Toner?](https://support.ldproducts.com/en_us/which-brother-printers-use-tn637-toner-SkV4Faa4bl?xid=tmd:blog:pdp&utm_medium=blog&utm_source=ldhelpcenter&utm_campaign=TN635_series:SJBibY2NWe) * [Do TN635 and TN637 Use the Same Drum?](https://support.ldproducts.com/en_us/do-tn635-and-tn637-use-the-same-drum-BJKC6pNbg?xid=tmd:blog:pdp&utm_medium=blog&utm_source=ldhelpcenter&utm_campaign=TN635_series:SJBibY2NWe) * [How to Check Remaining Part Life on Brother HL-L8430CDW?](https://support.ldproducts.com/en_us/how-to-check-remaining-part-life-on-brother-hl-l8430cdw-SySN_NHZe?xid=tmd:blog:pdp&utm_medium=blog&utm_source=ldhelpcenter&utm_campaign=TN635_series:SJBibY2NWe)